bump pointer: internal (lessons: analysis vs build plan)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.claude/CLAUDE.md

@@ -30,6 +30,7 @@
 - Stage explicit file lists; never `git add -A` or a directory. Pushing is the user's call.
 - New API responses need a typed DTO plus the parity fact. MCP vocabularies are generated from the wire types, never retyped.
 - Every route belongs in the route policy catalog; every new event type goes into the MCP resource catalog.
+- Workflow files under `.github/` go through zizmor before they are committed (`zizmor .` from the repository root, findings from severity low on): fix every finding or ignore it in `zizmor.yml` with a reason. The `zizmor` job in `action-pins.yml` runs the same check on every push.
 - The about, terms and privacy pages under `src/Web/autopilot-monitor-web/app/` state facts customers rely on: verify every claim against the code before writing it and update them in the same change as the fact they describe.
 
 ## Code Quality

.github/codeql/codeql-config.yml

@@ -1,8 +1,8 @@
 # CodeQL configuration.
 #
-# The default query suites stay active — this file only filters out two C# queries
-# that fire structurally on this codebase, where the flagged behavior is the feature,
-# not a defect:
+# The default query suites stay active — this file only filters out queries that
+# fire structurally on this codebase, where the flagged behavior is the feature
+# or the protection exists in a form the query cannot see:
 #
 #   cs/exposure-of-sensitive-information
 #     Audit and operational logs record WHO performed an action (actor UPN / email)
@@ -15,10 +15,20 @@
 #     key. The IP is an identifier for throttling, not a secret at rest; storing it in
 #     the in-memory / table rate-limit key is by design.
 #
+#   js/missing-rate-limiting
+#     Only the MCP server has Express routes. Every one that does work is throttled by
+#     our own limiters (oauthRateLimit / oauthTokenRateLimit on /oauth/*, accessGuard
+#     on /mcp); /health and the OAuth discovery documents return static JSON.
+#     The query only recognizes limiters from npm packages (express-rate-limit and
+#     similar) and flags a route handler as soon as it calls a function named
+#     like *auth*, *login* or *verify*. So it reports throttled and unthrottled
+#     routes the same way, and every alert it ever raised was a false positive. The
+#     coverage check it stood in for is a test: every OAuth router route must carry
+#     a limiter or be named as exempt (MCP oauth-rate-limit.test.ts).
+#
 # Genuine one-off false positives from OTHER queries (e.g. an open-redirect the taint
-# model can't see is allow-listed, a rate-limited route it doesn't recognize) are
-# dismissed individually in the Security tab so those queries stay sharp — they are
-# NOT suppressed here.
+# model can't see is allow-listed) are dismissed individually in the Security tab so
+# those queries stay sharp — they are NOT suppressed here.
 #
 # Log-injection (cs/log-forging) is deliberately NOT filtered: user-controlled values
 # are sanitized at the sink via Helpers/LogSanitizer, so the query stays useful for
@@ -29,3 +39,5 @@ query-filters:
       id: cs/exposure-of-sensitive-information
   - exclude:
       id: cs/cleartext-storage-of-sensitive-information
+  - exclude:
+      id: js/missing-rate-limiting

.github/dependabot.yml

@@ -1,5 +1,9 @@
 version: 2
 
+# Cooldown: a version is proposed only once it has been public for 7 days, so a
+# release that is yanked or found malicious within its first week never reaches a
+# PR. Security updates are exempt from the cooldown by Dependabot's own rules.
+#
 # Grouping: every ecosystem gets one batched PR for minor/patch version
 # updates and one batched PR for security updates. Groups apply to version
 # updates only by default, so the security-updates groups are declared
@@ -10,6 +14,8 @@ updates:
     directory: /
     schedule:
       interval: weekly
+    cooldown:
+      default-days: 7
     open-pull-requests-limit: 5
     groups:
       dotnet:
@@ -23,6 +29,8 @@ updates:
     directory: /src/Web/autopilot-monitor-web
     schedule:
       interval: weekly
+    cooldown:
+      default-days: 7
     open-pull-requests-limit: 5
     groups:
       web:
@@ -41,6 +49,8 @@ updates:
     directory: /src/McpServer/autopilot-monitor-mcp
     schedule:
       interval: weekly
+    cooldown:
+      default-days: 7
     open-pull-requests-limit: 5
     groups:
       mcp:
@@ -55,10 +65,32 @@ updates:
       - dependency-name: '*'
         update-types: ['version-update:semver-major']
 
+  # Validator tooling for rules/ (ajv for validate.js); combine-rules.yml installs it from this
+  # lockfile with contents:write in hand, so the pins must not go stale.
+  - package-ecosystem: npm
+    directory: /rules/scripts
+    schedule:
+      interval: weekly
+    cooldown:
+      default-days: 7
+    open-pull-requests-limit: 5
+    groups:
+      rules-tooling:
+        patterns: ['*']
+      rules-tooling-security:
+        applies-to: security-updates
+        patterns: ['*']
+
+  # Every action is referenced by commit SHA with the version in a trailing comment;
+  # action-pins.yml fails any workflow change that reintroduces a mutable tag. Dependabot
+  # is what keeps those pins current: it rewrites the SHA and the comment together, so the
+  # pins are reviewed in a PR instead of drifting silently or being bumped by hand.
   - package-ecosystem: github-actions
     directory: /
     schedule:
       interval: monthly
+    cooldown:
+      default-days: 7
     groups:
       actions:
         patterns: ['*']

.github/scripts/Get-StorageAuthHeaders.ps1

@@ -0,0 +1,61 @@
+<#
+.SYNOPSIS
+    Returns the request headers that authorize an Azure Storage REST call with Microsoft Entra.
+
+.DESCRIPTION
+    One place for the storage OAuth contract shared by every publisher in this repo -- the
+    agent ZIP and MSI, the customer bootstrap scripts, the version manifests and the build
+    counters. Resource id, the az invocation, the service version and the failure message
+    live here so they cannot drift between call sites.
+
+    Identity comes from whatever `az login` established: the federated GitHub OIDC principal
+    in CI (azure/login, subject repo:okieselbach/AutopilotMonitor:ref:refs/heads/main), the
+    operator's own account for the local build. No secret is read, stored or passed around.
+    Under GitHub Actions the token is masked in the run log before it is returned.
+
+    x-ms-version is MANDATORY here, not decoration: Entra-authorized requests are rejected
+    below 2017-11-09, and Table requests without a SAS must carry the header at all. 2021-08-06
+    is old enough to be deployed in every region and new enough for everything we send.
+
+    Callers merge the result into their own headers -- `$auth + @{ ... }` yields a new
+    hashtable per request, so nothing is shared across uploads:
+
+        $auth = & "$PSScriptRoot/Get-StorageAuthHeaders.ps1"
+        Invoke-RestMethod -Uri $url -Method Put -Headers ($auth + @{ 'x-ms-blob-type' = 'BlockBlob' }) -Body $bytes
+
+    Acquire once per step and reuse: every call shells out to az (~1s) and the token is valid
+    for the lifetime of a job.
+
+.OUTPUTS
+    [hashtable] Authorization + x-ms-version.
+#>
+[CmdletBinding()]
+param()
+
+$ErrorActionPreference = 'Stop'
+
+# The data-plane resource, not management.azure.com -- a management token is accepted by
+# neither the blob nor the table endpoint.
+$token = az account get-access-token --resource https://storage.azure.com --query accessToken -o tsv 2>$null
+
+if ($LASTEXITCODE -ne 0 -or [string]::IsNullOrWhiteSpace($token)) {
+    throw ('Could not acquire an Azure Storage token. In CI this means the azure/login step ' +
+           'is missing or its federated credential does not cover this ref; locally, run ' +
+           '`az login`. A token alone is not enough: the principal also needs Storage Blob ' +
+           'Data Contributor on the container it writes, and Storage Table Data Contributor ' +
+           'on the table -- a missing role shows up later as HTTP 403 AuthorizationPermissionMismatch.')
+}
+
+# GitHub masks only secrets.* on its own; a token minted at run time is clear text in the
+# (public) run log the moment anything prints it -- an uncaptured call of this script, or
+# Get-Error / Format-List on a failed request, whose TargetObject carries this header.
+# Write-Host, never Write-Output: the output stream is this script's return value. Only
+# under Actions -- anywhere else the line would print the token instead of hiding it.
+if ($env:GITHUB_ACTIONS -eq 'true') {
+    Write-Host "::add-mask::$token"
+}
+
+return @{
+    'Authorization' = "Bearer $token"
+    'x-ms-version'  = '2021-08-06'
+}

.github/scripts/Publish-BootstrapScripts.ps1

@@ -12,52 +12,78 @@
                                 lands a consistent set (ZIP + manifest + scripts).
 
     Both callers run the same code. The scripts on the download alias are the live
-    copy the WDP bootstrap MSI (Invoke-BootstrapDownload.ps1) downloads on every
-    enrolling device, so "current" is a correctness property, not cosmetics.
+    copy the stage-1 loader downloads on every enrolling device, whether it came from
+    Intune or from the bootstrap MSI, so "current" is a correctness property, not
+    cosmetics.
 
     Steps, in order:
-      1. Parse $ScriptVersion from the bootstrap source.
-      2. Render the -Dev variant by literal substitution of the two URL/manifest
+      1. Parse $ScriptVersion from the loader and the bootstrap source.
+      2. Render the -Dev variants by literal substitution of the URL/manifest
          defaults. A missing anchor is a hard failure -- a silently un-substituted
          dev script would point the dev fleet at the stable agent.
-      3. Version-bump guard: if the published bootstrap differs from the source
-         but carries the same $ScriptVersion, abort. Otherwise the docs badge,
+      3. Version-bump guard: if a published script differs from its source but
+         carries the same $ScriptVersion, abort. Otherwise the docs badge,
          version.json.bootstrapVersion and the portal's "your script is outdated"
          hint would all keep asserting a version that is no longer what ships.
-      4. Upload every script blob with Cache-Control: no-cache (they rotate in
+      4. Build the publish set (loader, bootstrap, both dev renders, the extras).
+      5. Authenticode-sign every script (see -SigningToken). Signing is the LAST
+         transformation: it covers the exact CRLF/UTF-8 bytes that get uploaded,
+         and nothing may touch them afterwards or the signature breaks.
+      6. Upload every script blob with Cache-Control: no-cache (they rotate in
          place), mirrored fail-soft to the legacy account.
-      5. Reconcile the two version oracles: version.json.bootstrapVersion
-         (read-modify-write under If-Match, so a concurrent agent release cannot
-         lose its agent fields) and AdminConfiguration.LatestBootstrapV2ScriptVersion.
-      6. Verify through the alias -- re-download each blob and compare SHA-256.
+      7. Reconcile the version oracles: version.json.bootstrapVersion and
+         .loaderVersion (read-modify-write under If-Match, so a concurrent agent
+         release cannot lose its agent fields) and
+         AdminConfiguration.LatestBootstrapV2ScriptVersion.
+      8. Verify through the alias -- re-download each blob and compare SHA-256.
 
-.PARAMETER SasToken
-    Container SAS for the eu storage account with write permission. Leading '?' tolerated.
+    Comparisons against a published script always strip its signature block first
+    (Get-ComparableText). A signature carries a timestamp, so signed bytes differ on
+    every run; without stripping, the bump guard and the drift check would report a
+    change for every unchanged script.
 
 .PARAMETER LegacySasToken
     Container SAS for the legacy account. Optional -- a mirror failure warns, never fails.
-
-.PARAMETER TableSasToken
-    Table SAS for AdminConfiguration. Optional -- omitted or 'XXX' skips the oracle update.
+    The legacy account lives in a different tenant, so the ambient Entra identity cannot
+    reach it; this is the only credential the publisher still takes.
 
 .PARAMETER RepoRoot
     Repository root. Defaults to the parent of .github/scripts.
 
 .PARAMETER DryRun
-    Run every check and render, upload nothing.
+    Run every check and render, upload nothing. A dry run signs when a token is supplied
+    and skips signing when it is not: the PR gate runs this without any Azure login.
+
+.PARAMETER SigningToken
+    Azure Key Vault access token for AzureSignTool. MANDATORY for a real publish -- an
+    unsigned customer script is not something this repo publishes. Together with
+    -KeyVaultUrl and -CertificateName.
+
+.PARAMETER ExpectedPublisher
+    Optional -like pattern the signer subject must match after signing. Pins the publisher
+    instead of accepting any trusted signature; the loader on the device pins the same way.
+
+.PARAMETER SignedOutputDir
+    Optional directory that receives a copy of every published file exactly as uploaded.
+    Used by CI to offer the signed scripts as a build artifact for local inspection.
 
 .EXAMPLE
     ./Publish-BootstrapScripts.ps1 -DryRun
 
 .EXAMPLE
-    ./Publish-BootstrapScripts.ps1 -SasToken $env:SAS -TableSasToken $env:TABLE_SAS
+    ./Publish-BootstrapScripts.ps1 -LegacySasToken $env:LEGACY_SAS -SigningToken $env:AKV_TOKEN `
+        -KeyVaultUrl $env:KV_URL -CertificateName $env:CERT
 #>
 [CmdletBinding()]
 param(
-    [string]$SasToken,
     [string]$LegacySasToken,
-    [string]$TableSasToken,
     [string]$RepoRoot,
+    [string]$SigningToken,
+    [string]$KeyVaultUrl,
+    [string]$CertificateName,
+    [string]$TimestampUrl = 'http://timestamp.acs.microsoft.com',
+    [string]$ExpectedPublisher,
+    [string]$SignedOutputDir,
     [switch]$DryRun
 )
 
@@ -66,9 +92,6 @@ $ErrorActionPreference = 'Stop'
 if (-not $RepoRoot) {
     $RepoRoot = (Resolve-Path (Join-Path $PSScriptRoot '../..')).Path
 }
-if (-not $DryRun -and [string]::IsNullOrWhiteSpace($SasToken)) {
-    throw 'SasToken is required unless -DryRun is used.'
-}
 
 $ContainerUrl       = 'https://autopilotmonitoreu.blob.core.windows.net/agent'
 $LegacyContainerUrl = 'https://autopilotmonitor.blob.core.windows.net/agent'
@@ -78,8 +101,23 @@ $TableUrl           = "https://autopilotmonitoreu.table.core.windows.net/AdminCo
 $BootstrapSource   = Join-Path $RepoRoot 'scripts/Bootstrap/Install-AutopilotMonitor.ps1'
 $BootstrapBlob     = 'Install-AutopilotMonitor.ps1'
 $DevBlob           = 'Install-AutopilotMonitor-Dev.ps1'
+# Stage 1. Assigned in Intune once, and embedded in the bootstrap MSI; it downloads the
+# bootstrap above on every device and verifies its publisher before running it.
+$LoaderSource      = Join-Path $RepoRoot 'scripts/Bootstrap/Start-AutopilotMonitor.ps1'
+$LoaderBlob        = 'Start-AutopilotMonitor.ps1'
+$LoaderDevBlob     = 'Start-AutopilotMonitor-Dev.ps1'
 $ScriptContentType = 'text/plain; charset=utf-8'
 
+$SigningEnabled = -not [string]::IsNullOrWhiteSpace($SigningToken)
+if (-not $DryRun -and -not $SigningEnabled) {
+    throw ('Publishing requires -SigningToken (plus -KeyVaultUrl and -CertificateName): the ' +
+           'loader on every device verifies the publisher of what it downloads, so an unsigned ' +
+           'script would be rejected in the field. Only -DryRun may run without signing.')
+}
+if ($SigningEnabled -and ([string]::IsNullOrWhiteSpace($KeyVaultUrl) -or [string]::IsNullOrWhiteSpace($CertificateName))) {
+    throw '-SigningToken needs -KeyVaultUrl and -CertificateName.'
+}
+
 function Get-HttpStatus {
     param($ErrorRecord)
     if ($ErrorRecord.Exception.PSObject.Properties['Response'] -and $ErrorRecord.Exception.Response) {
@@ -125,6 +163,132 @@ function Get-PublishBytes {
     return ,(New-Object System.Text.UTF8Encoding $false).GetBytes($normalised)
 }
 
+# A PowerShell signature is appended as a comment block at the end of the file, so the
+# published bytes are "source + signature". Everything that compares a published script to
+# its source has to cut that block off first -- the signature carries a timestamp and is
+# therefore different on every publish, while the script above it is unchanged.
+function Remove-SignatureBlock {
+    param([string]$Text)
+    $marker = '# SIG # Begin signature block'
+    $index = $Text.IndexOf($marker)
+    if ($index -lt 0) { return $Text }
+    return $Text.Substring(0, $index)
+}
+
+# Comparison form: no signature, LF, no trailing blank lines. Used for "is the published
+# copy still this source" -- never for what gets uploaded.
+function Get-ComparableText {
+    param([string]$Text)
+    return (Remove-SignatureBlock $Text).Replace("`r`n", "`n").TrimEnd("`n")
+}
+
+# Signs the publish set in place: each item's bytes are written to a work directory, signed
+# there, verified, and read back as the bytes that will be uploaded. Signing has to be the
+# last transformation -- the signature covers exactly these bytes, so nothing may normalise
+# or re-encode them afterwards.
+function Set-PublishSetSignature {
+    param([object[]]$Items, [string]$WorkDir)
+
+    if (-not (Get-Command azuresigntool -ErrorAction SilentlyContinue)) {
+        throw "azuresigntool is not on PATH. Install it with: dotnet tool install --global AzureSignTool --version 7.0.1"
+    }
+
+    New-Item -ItemType Directory -Force -Path $WorkDir | Out-Null
+
+    $paths = @()
+    foreach ($item in $Items) {
+        $path = Join-Path $WorkDir $item.BlobName
+        [System.IO.File]::WriteAllBytes($path, [byte[]]$item.Bytes)
+        $paths += $path
+    }
+
+    Write-Host "Signing $($paths.Count) script(s) with certificate '$CertificateName'..."
+    & azuresigntool.exe sign --verbose `
+        --azure-key-vault-url $KeyVaultUrl `
+        --azure-key-vault-accesstoken $SigningToken `
+        --azure-key-vault-certificate $CertificateName `
+        --timestamp-rfc3161 $TimestampUrl `
+        --file-digest sha256 `
+        --description 'Autopilot Monitor bootstrap' `
+        --description-url 'https://www.autopilotmonitor.com' `
+        $paths
+
+    # Native tool: PowerShell does not throw on a non-zero exit, and an unnoticed signing
+    # failure would publish unsigned scripts that every loader in the field then rejects.
+    if ($LASTEXITCODE -ne 0) {
+        throw "azuresigntool failed with exit code $LASTEXITCODE -- nothing was uploaded."
+    }
+
+    foreach ($item in $Items) {
+        $path = Join-Path $WorkDir $item.BlobName
+        $sig = Get-AuthenticodeSignature -FilePath $path
+        if ($sig.Status -ne 'Valid') {
+            throw "Signature on $($item.BlobName) is '$($sig.Status)', expected 'Valid'."
+        }
+        # Without a timestamp the signature dies with the certificate, and these scripts sit
+        # on customer devices far longer than a certificate lifetime.
+        if (-not $sig.TimeStamperCertificate) {
+            throw "Signature on $($item.BlobName) carries no timestamp."
+        }
+        if ($ExpectedPublisher -and $sig.SignerCertificate.Subject -notlike $ExpectedPublisher) {
+            throw "$($item.BlobName) was signed by '$($sig.SignerCertificate.Subject)', expected '$ExpectedPublisher'."
+        }
+        # Plain assignment, NO comma operator: the ',' elsewhere in this file exists because
+        # PowerShell unrolls an array RETURNED from a function, which is not what a property
+        # assignment does -- here it would wrap the byte[] in an Object[] of length 1 and the
+        # upload would fail converting it back.
+        $signedBytes = [System.IO.File]::ReadAllBytes($path)
+        if ($signedBytes.Length -le $item.Bytes.Length) {
+            throw ("Signed $($item.BlobName) is $($signedBytes.Length) bytes but the unsigned form " +
+                   "was $($item.Bytes.Length) -- a signature only ever adds bytes, so this is a " +
+                   'read-back bug, not a signing result.')
+        }
+        $item.Bytes = $signedBytes
+        Write-Host "  signed $($item.BlobName) ($($signedBytes.Length) bytes, signer $($sig.SignerCertificate.Subject.Split(',')[0]))"
+    }
+}
+
+# Aborts when a published script changed behaviour without a version bump. Consumers act on
+# the version (docs badge, version.json, the portal's outdated-script hint), so an unchanged
+# version has to mean unchanged behaviour.
+function Assert-VersionBump {
+    param(
+        [string]$BlobName,
+        [string]$SourceContent,
+        [string]$SourceOrigin,
+        [string]$SourceVersion
+    )
+
+    $publishedBytes = Get-PublishedBytes "$AliasUrl/$BlobName"
+    if ($null -eq $publishedBytes) {
+        Write-Host "No published $BlobName yet -- version-bump guard skipped (first publish)"
+        return
+    }
+
+    $publishedText = [System.Text.Encoding]::UTF8.GetString($publishedBytes)
+    if ((Get-ComparableText $publishedText) -eq (Get-ComparableText $SourceContent)) {
+        Write-Host "Published $BlobName is already this source (signature block aside)"
+        return
+    }
+
+    $publishedVersion = Get-BootstrapScriptVersion -Content $publishedText -Origin "$AliasUrl/$BlobName" -Optional
+
+    if ($null -eq $publishedVersion) {
+        Write-Host "::warning::The published $BlobName is not a readable script (no ScriptVersion found). Republishing over it."
+    } elseif ($publishedVersion -ne $SourceVersion) {
+        Write-Host "Version bump: $publishedVersion -> $SourceVersion ($BlobName)"
+    } elseif ((Get-CodeFingerprint -Text (Remove-SignatureBlock $publishedText) -Origin "$AliasUrl/$BlobName") -eq
+              (Get-CodeFingerprint -Text $SourceContent -Origin $SourceOrigin)) {
+        # Comments, typos in comments, reflow -- nothing a consumer of the version can act on.
+        Write-Host "::warning::$BlobName changed in comments or formatting only; publishing under the unchanged version $SourceVersion."
+    } else {
+        throw ("Version-bump guard: $BlobName changed behaviour but ScriptVersion is still $SourceVersion. " +
+               "Bump it in $SourceOrigin -- the docs badge, version.json and the " +
+               'portal outdated-script hint all read that value, and customers decide from it whether ' +
+               'to re-upload their Intune copy. Comment-only and formatting changes do not need a bump.')
+    }
+}
+
 function Get-BootstrapScriptVersion {
     param([string]$Content, [string]$Origin, [switch]$Optional)
     if ($Content -match '\$ScriptVersion\s*=\s*"([\d\.\-a-zA-Z]+)"') { return $Matches[1] }
@@ -152,12 +316,16 @@ function Get-CodeFingerprint {
     return (($tokens | Where-Object { $ignored -notcontains $_.Kind.ToString() } | ForEach-Object { $_.Text }) -join "`n")
 }
 
-# ------------------------------------------------------------------ 1. source
+# ------------------------------------------------------------------ 1. sources
 $sourceContent = Get-Content $BootstrapSource -Raw
 $sourceBytes   = Get-PublishBytes $sourceContent
 $scriptVersion = Get-BootstrapScriptVersion -Content $sourceContent -Origin $BootstrapSource
 Write-Host "Bootstrap script version: $scriptVersion"
 
+$loaderContent = Get-Content $LoaderSource -Raw
+$loaderVersion = Get-BootstrapScriptVersion -Content $loaderContent -Origin $LoaderSource
+Write-Host "Loader script version: $loaderVersion"
+
 # ------------------------------------------------------------------ 2. dev render
 $stableUrlLiteral = '$AgentDownloadUrl = "https://download.autopilotmonitor.com/agent/AutopilotMonitor-Agent.zip"'
 $devUrlLiteral    = '$AgentDownloadUrl = "https://download.autopilotmonitor.com/agent/AutopilotMonitor-Agent-dev.zip"'
@@ -170,33 +338,21 @@ if ($sourceContent.IndexOf($stableUrlLiteral) -lt 0 -or $sourceContent.IndexOf($
 $devContent = $sourceContent.Replace($stableUrlLiteral, $devUrlLiteral).Replace($stableManLiteral, $devManLiteral)
 Write-Host "Rendered $DevBlob (dev agent URL + version-dev.json)"
 
-# ------------------------------------------------------------------ 3. bump guard
-$publishedBytes = Get-PublishedBytes "$AliasUrl/$BootstrapBlob"
-if ($null -eq $publishedBytes) {
-    Write-Host 'No published bootstrap yet -- version-bump guard skipped (first publish)'
-} elseif ((Get-Sha256 $publishedBytes) -eq (Get-Sha256 $sourceBytes)) {
-    Write-Host 'Published bootstrap is already byte-identical to the source'
-} else {
-    $publishedText    = [System.Text.Encoding]::UTF8.GetString($publishedBytes)
-    $publishedVersion = Get-BootstrapScriptVersion -Content $publishedText -Origin "$AliasUrl/$BootstrapBlob" -Optional
+# The dev loader must fetch the dev bootstrap, or a dev device would run the stable chain.
+$stableLoaderLiteral = '$BootstrapUrl = "https://download.autopilotmonitor.com/agent/Install-AutopilotMonitor.ps1"'
+$devLoaderLiteral    = '$BootstrapUrl = "https://download.autopilotmonitor.com/agent/Install-AutopilotMonitor-Dev.ps1"'
 
-    if ($null -eq $publishedVersion) {
-        Write-Host "::warning::The published $BootstrapBlob is not a readable bootstrap script (no ScriptVersion found). Republishing over it."
-    } elseif ($publishedVersion -ne $scriptVersion) {
-        Write-Host "Version bump: $publishedVersion -> $scriptVersion"
-    } elseif ((Get-CodeFingerprint -Text $publishedText -Origin "$AliasUrl/$BootstrapBlob") -eq
-              (Get-CodeFingerprint -Text $sourceContent -Origin $BootstrapSource)) {
-        # Comments, typos in comments, reflow -- nothing a consumer of the version can act on.
-        Write-Host "::warning::$BootstrapBlob changed in comments or formatting only; publishing under the unchanged version $scriptVersion."
-    } else {
-        throw ("Version-bump guard: $BootstrapBlob changed behaviour but ScriptVersion is still $scriptVersion. " +
-               "Bump it in $BootstrapSource -- the docs badge, version.json.bootstrapVersion and the " +
-               'portal outdated-script hint all read that value, and customers decide from it whether ' +
-               'to re-upload their Intune copy. Comment-only and formatting changes do not need a bump.')
-    }
+if ($loaderContent.IndexOf($stableLoaderLiteral) -lt 0) {
+    throw "Loader dev-render: anchor literal missing in $LoaderSource"
 }
+$devLoaderContent = $loaderContent.Replace($stableLoaderLiteral, $devLoaderLiteral)
+Write-Host "Rendered $LoaderDevBlob (points at $DevBlob)"
 
-# ------------------------------------------------------------------ 4. upload
+# ------------------------------------------------------------------ 3. bump guards
+Assert-VersionBump -BlobName $BootstrapBlob -SourceContent $sourceContent -SourceOrigin $BootstrapSource -SourceVersion $scriptVersion
+Assert-VersionBump -BlobName $LoaderBlob    -SourceContent $loaderContent -SourceOrigin $LoaderSource    -SourceVersion $loaderVersion
+
+# ------------------------------------------------------------------ 4. publish set
 # Sources beyond the bootstrap pair, read straight from the repo.
 $extraSources = @(
     @{ Path = 'scripts/Bootstrap/Test-ShouldBootstrapAgent.ps1';       BlobName = 'Test-ShouldBootstrapAgent.ps1' }
@@ -206,20 +362,38 @@ $extraSources = @(
 # Uninstall-AutopilotMonitor.ps1 is deliberately NOT published: nothing links it, and
 # an unauthenticated uninstall script on the public download host is not a feature.
 
+# Text is the unsigned publish form and stays the reference for every comparison against a
+# published copy; Bytes is what goes on the wire and carries the signature after step 4.
 $publishSet = [System.Collections.Generic.List[object]]::new()
-$publishSet.Add([pscustomobject]@{ BlobName = $BootstrapBlob; Bytes = $sourceBytes })
-$publishSet.Add([pscustomobject]@{ BlobName = $DevBlob;       Bytes = (Get-PublishBytes $devContent) })
+$publishSet.Add([pscustomobject]@{ BlobName = $LoaderBlob;    Text = $loaderContent;    Bytes = (Get-PublishBytes $loaderContent) })
+$publishSet.Add([pscustomobject]@{ BlobName = $LoaderDevBlob; Text = $devLoaderContent; Bytes = (Get-PublishBytes $devLoaderContent) })
+$publishSet.Add([pscustomobject]@{ BlobName = $BootstrapBlob; Text = $sourceContent;    Bytes = $sourceBytes })
+$publishSet.Add([pscustomobject]@{ BlobName = $DevBlob;       Text = $devContent;       Bytes = (Get-PublishBytes $devContent) })
 foreach ($extra in $extraSources) {
     $extraPath = Join-Path $RepoRoot $extra.Path
     if (-not (Test-Path $extraPath)) {
         throw "Publish source missing: $extraPath"
     }
-    $publishSet.Add([pscustomobject]@{ BlobName = $extra.BlobName; Bytes = (Get-PublishBytes (Get-Content $extraPath -Raw)) })
+    $extraText = Get-Content $extraPath -Raw
+    $publishSet.Add([pscustomobject]@{ BlobName = $extra.BlobName; Text = $extraText; Bytes = (Get-PublishBytes $extraText) })
+}
+
+# ------------------------------------------------------------------ 5. sign
+# After this point the bytes are final. Normalising, re-encoding or rewriting a line ending
+# would invalidate the signature, and the device-side loader would refuse the script.
+if ($SigningEnabled) {
+    Set-PublishSetSignature -Items $publishSet -WorkDir (Join-Path ([System.IO.Path]::GetTempPath()) "apm-publish-$PID")
+} else {
+    Write-Host '::warning::No signing token supplied -- dry run continues with unsigned scripts.'
 }
 
 $legacySas = if ($LegacySasToken) { $LegacySasToken.TrimStart('?') } else { '' }
-$writeSas  = if ($SasToken) { $SasToken.TrimStart('?') } else { '' }
 
+# Acquired lazily: a dry run must stay runnable without any Azure login -- the PR gate
+# (bootstrap-script-gates.yml) executes this script with -DryRun and never logs in.
+$authHeaders = if ($DryRun) { $null } else { & (Join-Path $PSScriptRoot 'Get-StorageAuthHeaders.ps1') }
+
+# ------------------------------------------------------------------ 6. upload
 foreach ($item in $publishSet) {
     # Explicit type, not a convenience: an Object[] body is uploaded as space-separated
     # decimals rather than raw bytes, and every hash check still passes because [byte[]]
@@ -227,11 +401,21 @@ foreach ($item in $publishSet) {
     [byte[]]$bytes = $item.Bytes
     $item | Add-Member -NotePropertyName Sha256 -NotePropertyValue (Get-Sha256 $bytes) -Force
 
+    # Exactly the bytes that go on the wire, for the CI artifact. Written in a dry run too:
+    # that is the run an operator uses to inspect a signed script before it is published.
+    if ($SignedOutputDir) {
+        New-Item -ItemType Directory -Force -Path $SignedOutputDir | Out-Null
+        [System.IO.File]::WriteAllBytes((Join-Path $SignedOutputDir $item.BlobName), $bytes)
+    }
+
     if ($DryRun) {
-        # Doubles as a drift check: says per blob whether the alias already serves this source.
+        # Doubles as a drift check: says per blob whether the alias already serves this
+        # source. Compared as text without the signature block -- signed bytes differ on
+        # every run, so a byte comparison would report drift for every unchanged script.
         $served = Get-PublishedBytes "$AliasUrl/$($item.BlobName)"
         $state = if ($null -eq $served) { 'MISSING on the alias' }
-                 elseif ((Get-Sha256 $served) -eq $item.Sha256) { 'already current' }
+                 elseif ((Get-ComparableText ([System.Text.Encoding]::UTF8.GetString($served))) -eq
+                         (Get-ComparableText $item.Text)) { 'already current' }
                  else { 'STALE on the alias' }
         Write-Host "  [dry-run] $($item.BlobName) ($($bytes.Length) bytes, sha256 $($item.Sha256)) -- $state"
         continue
@@ -241,8 +425,18 @@ foreach ($item in $publishSet) {
     # with Front Door. Route caching is disabled there, but a stale script paired with a
     # fresh manifest would fail the bootstrap SHA check -- this keeps that class of bug
     # impossible even if caching is ever re-enabled.
-    $headers = @{ 'x-ms-blob-type' = 'BlockBlob'; 'Content-Type' = $ScriptContentType; 'x-ms-blob-cache-control' = 'no-cache' }
-    Invoke-RestMethod -Uri "$ContainerUrl/$($item.BlobName)?$writeSas" -Method Put -Headers $headers -Body $bytes | Out-Null
+    #
+    # Content-Disposition: without it a text/plain blob opens as a web page in every
+    # browser, and the documented "download the script" step silently becomes "copy this
+    # text". The header makes the link a download everywhere, and command-line clients
+    # (the loader, the MSI, curl) ignore it.
+    $headers = @{
+        'x-ms-blob-type'                = 'BlockBlob'
+        'Content-Type'                  = $ScriptContentType
+        'x-ms-blob-cache-control'       = 'no-cache'
+        'x-ms-blob-content-disposition' = ('attachment; filename="{0}"' -f $item.BlobName)
+    }
+    Invoke-RestMethod -Uri "$ContainerUrl/$($item.BlobName)" -Method Put -Headers ($authHeaders + $headers) -Body $bytes | Out-Null
 
     # Read straight back from the blob (authoritative, no CDN in the way) before touching the
     # mirror or the next file. The alias verification at the end would catch a bad body too,
@@ -266,7 +460,7 @@ foreach ($item in $publishSet) {
     }
 }
 
-# ------------------------------------------------------------------ 5. version oracles
+# ------------------------------------------------------------------ 7. version oracles
 # version.json is the agent manifest; only bootstrapVersion belongs to us. Read from the
 # blob (not the alias) for an authoritative ETag, write back under If-Match so a concurrent
 # agent release cannot lose its version/sha256 fields.
@@ -278,11 +472,15 @@ if (-not $DryRun) {
         } else { [string]$manifestResp.Content }
         $manifest = $manifestRaw | ConvertFrom-Json
 
-        if ($manifest.bootstrapVersion -eq $scriptVersion) {
-            Write-Host "version.json already reports bootstrapVersion $scriptVersion"
+        if ($manifest.bootstrapVersion -eq $scriptVersion -and $manifest.loaderVersion -eq $loaderVersion) {
+            Write-Host "version.json already reports bootstrapVersion $scriptVersion and loaderVersion $loaderVersion"
         } else {
             $etag = '"' + ([string]($manifestResp.Headers['ETag'] | Select-Object -First 1)).Trim('"') + '"'
             $manifest | Add-Member -NotePropertyName 'bootstrapVersion' -NotePropertyValue $scriptVersion -Force
+            # Additive: no consumer reads loaderVersion yet. It exists so support can tell
+            # which stage-1 file a device was assigned -- stage 2 is always current by
+            # construction, so its version says nothing about the customer's Intune copy.
+            $manifest | Add-Member -NotePropertyName 'loaderVersion' -NotePropertyValue $loaderVersion -Force
             $body = [System.Text.Encoding]::UTF8.GetBytes(($manifest | ConvertTo-Json -Compress))
             $manifestHeaders = @{
                 'x-ms-blob-type'          = 'BlockBlob'
@@ -290,8 +488,8 @@ if (-not $DryRun) {
                 'x-ms-blob-cache-control' = 'no-cache'
                 'If-Match'                = $etag
             }
-            Invoke-RestMethod -Uri "$ContainerUrl/version.json?$writeSas" -Method Put -Headers $manifestHeaders -Body $body | Out-Null
-            Write-Host "version.json bootstrapVersion -> $scriptVersion (agent fields untouched)"
+            Invoke-RestMethod -Uri "$ContainerUrl/version.json" -Method Put -Headers ($authHeaders + $manifestHeaders) -Body $body | Out-Null
+            Write-Host "version.json bootstrapVersion -> $scriptVersion, loaderVersion -> $loaderVersion (agent fields untouched)"
 
             if ($legacySas) {
                 try {
@@ -310,11 +508,8 @@ if (-not $DryRun) {
     }
 }
 
-$tableSas = if ($TableSasToken) { $TableSasToken.TrimStart('?') } else { '' }
 if ($DryRun) {
     Write-Host "  [dry-run] would set AdminConfiguration.LatestBootstrapV2ScriptVersion = $scriptVersion"
-} elseif ([string]::IsNullOrEmpty($tableSas) -or $tableSas -eq 'XXX') {
-    Write-Host 'SKIPPED: AdminConfiguration update -- set AZURE_TABLE_ADMIN_SAS_TOKEN to enable the portal version oracle'
 } else {
     $tableHeaders = @{
         'Content-Type' = 'application/json'
@@ -322,11 +517,11 @@ if ($DryRun) {
         'If-Match'     = '*'
     }
     $tableBody = @{ LatestBootstrapV2ScriptVersion = $scriptVersion } | ConvertTo-Json
-    Invoke-RestMethod -Uri "$TableUrl`?$tableSas" -Method Merge -Headers $tableHeaders -Body $tableBody | Out-Null
+    Invoke-RestMethod -Uri $TableUrl -Method Merge -Headers ($authHeaders + $tableHeaders) -Body $tableBody | Out-Null
     Write-Host "AdminConfiguration.LatestBootstrapV2ScriptVersion = $scriptVersion"
 }
 
-# ------------------------------------------------------------------ 6. verify via alias
+# ------------------------------------------------------------------ 8. verify via alias
 if (-not $DryRun) {
     $pending = [System.Collections.ArrayList]::new()
     $publishSet | ForEach-Object { [void]$pending.Add($_) }
@@ -358,7 +553,8 @@ if ($env:GITHUB_STEP_SUMMARY) {
     $summary = @(
         "### Bootstrap scripts: $mode",
         '',
-        "Bootstrap script version: **$scriptVersion**",
+        "Loader script version: **$loaderVersion** | Bootstrap script version: **$scriptVersion**",
+        "Signed: **$(if ($SigningEnabled) { "yes, certificate '$CertificateName'" } else { 'NO (unsigned dry run)' })**",
         ''
     ) + ($publishSet | ForEach-Object { "- $($_.BlobName) -- sha256 $($_.Sha256)" })
     ($summary -join [Environment]::NewLine) | Out-File -FilePath $env:GITHUB_STEP_SUMMARY -Append -Encoding utf8

.github/scripts/Request-BuildNumber.ps1

@@ -12,7 +12,8 @@
     A failed build burns a number, which is harmless -- uniqueness matters,
     density does not.
 
-    The blob is public-read; only the write needs the container SAS.
+    The blob is public-read; only the write needs authorization, and that comes from the
+    ambient Entra identity (see Get-StorageAuthHeaders.ps1) -- no secret is passed in.
 
     Why a counter and not the published version manifest: manifests are written
     on publish, not on build (the agent writes version.json only for stable
@@ -20,10 +21,7 @@
     overwrite each other's versioned artifact.
 
 .PARAMETER CounterUrl
-    Full URL of the counter blob, without SAS.
-
-.PARAMETER SasToken
-    Container SAS with create+write permission. A leading '?' is tolerated.
+    Full URL of the counter blob.
 
 .PARAMETER Override
     Explicit build number instead of counter+1. If it is not greater than the
@@ -37,20 +35,19 @@
     [int] the reserved build number. Progress goes to the host, not the pipeline.
 
 .EXAMPLE
-    $n = ./Request-BuildNumber.ps1 -CounterUrl $url -SasToken $sas
+    $n = ./Request-BuildNumber.ps1 -CounterUrl $url
 #>
 [CmdletBinding()]
 param(
     [Parameter(Mandatory = $true)][string]$CounterUrl,
-    [Parameter(Mandatory = $true)][string]$SasToken,
     [int]$Override = 0,
     [int]$MaxAttempts = 5
 )
 
 $ErrorActionPreference = 'Stop'
 
-# Tolerate both secret formats ("sp=cw&..." and "?sp=cw&...").
-$writeUrl = $CounterUrl + '?' + $SasToken.TrimStart('?')
+# The write is Entra-authorized; the read below stays anonymous (public container).
+$authHeaders = & (Join-Path $PSScriptRoot 'Get-StorageAuthHeaders.ps1')
 
 function Get-HttpStatus {
     param($ErrorRecord)
@@ -85,8 +82,8 @@ for ($attempt = 1; $attempt -le $MaxAttempts; $attempt++) {
     $target = if ($Override -gt 0) { $Override } else { $counter.Value + 1 }
 
     try {
-        $headers = @{ 'x-ms-blob-type' = 'BlockBlob'; 'If-Match' = $counter.ETag }
-        Invoke-RestMethod -Uri $writeUrl -Method Put -Headers $headers -Body "$target" -ContentType 'text/plain' | Out-Null
+        $headers = $authHeaders + @{ 'x-ms-blob-type' = 'BlockBlob'; 'If-Match' = $counter.ETag }
+        Invoke-RestMethod -Uri $CounterUrl -Method Put -Headers $headers -Body "$target" -ContentType 'text/plain' | Out-Null
         Write-Host "  Reserved build number $target (CAS write ok, attempt $attempt)"
         return $target
     } catch {

.github/workflows/action-pins.yml

@@ -0,0 +1,108 @@
+name: Workflow gates
+
+# Two checks over the workflow files themselves:
+#   * verify-pins -- every third-party action is referenced by a full commit SHA plus a
+#                    version comment (stricter than zizmor's unpinned-uses audit).
+#   * zizmor      -- static analysis of every workflow (permissions, credential
+#                    persistence, template injection, ...). Configuration and the
+#                    reasoned ignores live in zizmor.yml at the repository root; the
+#                    same run is expected locally before a workflow change is committed.
+#
+# Every third-party action must be referenced by a full commit SHA, never by a tag.
+# Tags are mutable: whoever controls an action repository can repoint v4 at new code,
+# and that code runs inside jobs that hold the code-signing identity, the storage
+# credentials and a token that can push to main. A SHA is the only reference an
+# upstream owner cannot change under us.
+#
+# Lives in its own workflow rather than in ci.yml: CI deliberately ignores changes to
+# the other workflow files, so a guard placed there would stay silent for exactly the
+# commits it needs to inspect. Dependabot's action-pin PRs are the main customer: they
+# rewrite workflow files without anyone running zizmor locally.
+#
+# Like CI, this reports rather than blocks: main is deliberately unprotected, so a red
+# run is a signal to act on, not a merge barrier. Making it binding means adding
+# 'Verify action pins' as a required status check -- a branch-protection decision, not
+# something this file can assert.
+#
+# The pins are not maintained by hand — .github/dependabot.yml opens a monthly grouped
+# PR that rewrites both the SHA and the trailing version comment. The comment is
+# therefore required too: it is what makes a pinned line reviewable. It names the exact
+# release tag (# v7.0.1), never the floating major (# v7): a major tag moves with every
+# upstream release, after which the comment no longer names the pinned commit and
+# zizmor's ref-version-mismatch flags every line that carries it.
+
+on:
+  push:
+    branches: [main]
+    paths: ['.github/workflows/**', '.github/dependabot.yml', 'zizmor.yml']
+  pull_request:
+    branches: [main]
+    paths: ['.github/workflows/**', '.github/dependabot.yml', 'zizmor.yml']
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  verify-pins:
+    name: Verify action pins
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Every third-party action is pinned to a SHA
+        run: |
+          set -uo pipefail
+          failed=0
+          while IFS=: read -r file line ref; do
+            # Reusable workflows from this repository (workspace-relative ./ or the
+            # self-repository form $/) move with the commit that calls them, so there is
+            # nothing to pin.
+            case "$ref" in ./*|\$/*) continue ;; esac
+
+            if [[ "$ref" =~ ^[^@]+@[0-9a-f]{40}[[:space:]]+#[[:space:]]*v?[0-9]+\.[0-9]+\.[0-9]+([[:space:]]|$) ]]; then
+              printf 'ok  %s:%s  %s\n' "$file" "$line" "$ref"
+              continue
+            fi
+
+            if [[ "$ref" =~ ^[^@]+@[0-9a-f]{40}[[:space:]]*$ ]]; then
+              echo "::error file=$file,line=$line::Pinned but the version comment is missing: '$ref'. Write 'owner/action@<sha> # vX.Y.Z' so the line stays reviewable."
+            elif [[ "$ref" =~ ^[^@]+@[0-9a-f]{40}[[:space:]]+# ]]; then
+              echo "::error file=$file,line=$line::The version comment must name the exact release tag the SHA resolves to ('# vX.Y.Z'), not a floating major: '$ref'. Find it with: gh api repos/<owner>/<action>/git/matching-refs/tags/vN"
+            else
+              echo "::error file=$file,line=$line::Action '$ref' is not pinned to a commit SHA. Tags are mutable -- resolve it with: gh api repos/<owner>/<action>/git/ref/tags/<tag>"
+            fi
+            failed=1
+          # -H is load-bearing: with a single matching file grep omits the name, the
+          # fields shift by one and every diagnostic points at nothing.
+          done < <(grep -nHE '^[[:space:]]*(-[[:space:]]+)?uses:' .github/workflows/*.yml \
+                   | sed -E 's/^([^:]+):([0-9]+):[[:space:]]*(-[[:space:]]+)?uses:[[:space:]]*/\1:\2:/')
+
+          if [ "$failed" -ne 0 ]; then
+            echo "::error::Unpinned action references found -- fix them before this reaches main."
+            exit 1
+          fi
+          echo "All action references are pinned to commit SHAs."
+
+  zizmor:
+    name: zizmor audit
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      security-events: write   # SARIF upload: findings land in the Code scanning tab next to CodeQL
+      actions: read
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      # zizmor itself is version-pinned like every other tool here; bump it together with
+      # the local install so the gate and the pre-commit run agree on the finding set.
+      # Informational findings (template expansion of our own step outputs in pwsh) are
+      # visible locally but do not fail the gate.
+      - uses: zizmorcore/zizmor-action@cc914d7f3750a2d13d75c7f184a1060aa0e9d482 # v0.6.4
+        with:
+          version: 1.30.1
+          min-severity: low

.github/workflows/bootstrap-script-gates.yml

@@ -18,7 +18,9 @@ jobs:
     name: Bootstrap guard tests (PS 5.1)
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
       - name: Install Pester 5+
         shell: powershell

.github/workflows/build-agent.yml

@@ -57,6 +57,13 @@ env:
   VERSIONED_ZIP: AutopilotMonitor-Agent-v2.zip
   STABLE_ZIP: AutopilotMonitor-Agent.zip
   STABLE_MANIFEST: version.json
+  # Authenticode via Azure Key Vault; identity and vault come from repository variables.
+  # CODE_SIGN_EXPECTED_SUBJECT is optional and pins the publisher in the verify step.
+  CODE_SIGN_CLIENT_ID: ${{ vars.CODE_SIGN_CLIENT_ID }}
+  CODE_SIGN_CERTIFICATE_NAME: ${{ vars.CODE_SIGN_CERTIFICATE_NAME }}
+  CODE_SIGN_KEY_VAULT_URL: ${{ vars.CODE_SIGN_KEY_VAULT_URL }}
+  CODE_SIGN_EXPECTED_SUBJECT: ${{ vars.CODE_SIGN_EXPECTED_SUBJECT }}
+  CODE_SIGN_TIMESTAMP_URL: http://timestamp.acs.microsoft.com
 
 jobs:
   build:
@@ -65,14 +72,68 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      # Every released build is signed; a missing variable stops the run before a build
+      # number is burnt.
+      - name: Check code-signing configuration
+        shell: pwsh
+        run: |
+          foreach ($name in 'CODE_SIGN_CLIENT_ID', 'CODE_SIGN_CERTIFICATE_NAME', 'CODE_SIGN_KEY_VAULT_URL') {
+            if ([string]::IsNullOrWhiteSpace([Environment]::GetEnvironmentVariable($name))) {
+              throw "Repository variable $name is not set. Every released build must be Authenticode-signed."
+            }
+          }
+          Write-Host "Code-signing configuration present (certificate '$env:CODE_SIGN_CERTIFICATE_NAME')"
+
+      # Logs in FIRST and only to fetch the Key Vault token: azure/login sets the default az
+      # account, so the storage login below has to be the last one. Both federated credentials
+      # are bound to the ref, so this job must never be given an `environment:` -- that would
+      # change the OIDC subject claim and break both logins.
+      - name: Login to Azure (code-signing identity)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ env.CODE_SIGN_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          allow-no-subscriptions: true
+
+      - name: Acquire Key Vault token for signing
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $token = az account get-access-token --scope https://vault.azure.net/.default --query accessToken --output tsv
+          if ($LASTEXITCODE -ne 0 -or [string]::IsNullOrWhiteSpace($token)) {
+            throw "Could not acquire a Key Vault token for the code-signing identity."
+          }
+          Write-Host "::add-mask::$token"
+          "CODE_SIGN_AKV_ACCESS_TOKEN=$token" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+
+      # Every storage write below (counter blob, agent ZIP, manifests, AdminConfiguration)
+      # is authorized by this federated identity -- no SAS secret. One login covers the whole
+      # job: the federated credential is bound to the ref, and a release run takes ~2 minutes,
+      # well inside the token lifetime. Only the legacy mirror still needs a SAS: that account
+      # lives in the pre-migration tenant, where this principal has no identity.
+      - name: Login to Azure (OIDC)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
 
       # SDK 10 = single build toolchain (parity with local build.ps1 / global.json).
       - name: Setup .NET
-        uses: actions/setup-dotnet@v6
+        uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
         with:
           dotnet-version: '10.0.x'
 
+      # Version pinned; roll-forward because the tool targets an older runtime than the SDK above.
+      - name: Install AzureSignTool
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
+        run: dotnet tool install --no-cache --global AzureSignTool --version 7.0.1
+
       # Build numbers come from the shared counter blob -- one counter and one
       # implementation for CI and the local build (.github/scripts/Request-BuildNumber.ps1).
       # Reserve-before-build with ETag-CAS: concurrent builds can never mint the same
@@ -85,7 +146,6 @@ jobs:
         # build_number could otherwise break out of the quotes and run arbitrary code.
         env:
           BUILD_NUMBER_OVERRIDE: ${{ inputs.build_number }}
-          AGENT_SAS_TOKEN: ${{ secrets.AZURE_BLOB_AGENT_SAS_TOKEN }}
         run: |
           $override = 0
           if ($env:BUILD_NUMBER_OVERRIDE -ne '') {
@@ -96,7 +156,7 @@ jobs:
           }
 
           $counterUrl = "https://autopilotmonitoreu.blob.core.windows.net/agent/buildcounter-v$($env:LINE_MAJOR).txt"
-          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl $counterUrl -SasToken $env:AGENT_SAS_TOKEN -Override $override
+          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl $counterUrl -Override $override
 
           $csproj = Get-Content $env:CSPROJ_PATH -Raw
           if ($csproj -match '<VersionPrefix>(\d+\.\d+)</VersionPrefix>') {
@@ -129,6 +189,47 @@ jobs:
       - name: Run Agent unit tests
         run: dotnet test ${{ env.TEST_PROJECT }} --configuration Release --no-restore --verbosity quiet
 
+      # Authenticode over everything we author; third-party assemblies keep their own signature.
+      #
+      # THE POSITION IS LOAD-BEARING: signing rewrites the PE file, so it must run before the
+      # ZIP and every SHA-256 in the next step -- those hashes are the bootstrap's integrity
+      # oracle, and hashes taken before signing match no downloaded file.
+      #
+      # $LASTEXITCODE is checked explicitly: PowerShell does not throw on a native non-zero exit.
+      - name: Sign agent binaries (Authenticode)
+        shell: pwsh
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
+        run: |
+          $ErrorActionPreference = 'Stop'
+
+          $targets = @()
+          $targets += Get-ChildItem -Path "$env:AGENT_OUTPUT/*" -Include 'AutopilotMonitor.*.exe', 'AutopilotMonitor.*.dll' -File
+          $targets += Get-ChildItem -Path "$env:DIALOG_OUTPUT/AutopilotMonitor.SummaryDialog.exe" -File
+
+          if (-not ($targets | Where-Object Name -eq 'AutopilotMonitor.Agent.exe')) {
+            throw "AutopilotMonitor.Agent.exe not found in $env:AGENT_OUTPUT -- nothing to sign."
+          }
+          if (-not ($targets | Where-Object Name -eq 'AutopilotMonitor.SummaryDialog.exe')) {
+            throw "AutopilotMonitor.SummaryDialog.exe not found in $env:DIALOG_OUTPUT -- nothing to sign."
+          }
+
+          $targets | ForEach-Object { Write-Host "Signing $($_.Name)" }
+
+          & azuresigntool.exe sign --verbose `
+            --azure-key-vault-url "$env:CODE_SIGN_KEY_VAULT_URL" `
+            --azure-key-vault-accesstoken "$env:CODE_SIGN_AKV_ACCESS_TOKEN" `
+            --azure-key-vault-certificate "$env:CODE_SIGN_CERTIFICATE_NAME" `
+            --timestamp-rfc3161 "$env:CODE_SIGN_TIMESTAMP_URL" `
+            --file-digest sha256 `
+            --description "Autopilot Monitor Agent" `
+            --description-url "https://www.autopilotmonitor.com" `
+            ($targets | ForEach-Object { $_.FullName })
+
+          if ($LASTEXITCODE -ne 0) {
+            throw "azuresigntool failed with exit code $LASTEXITCODE -- aborting before anything is published."
+          }
+
       - name: Create release artifact
         id: artifact
         shell: pwsh
@@ -219,12 +320,57 @@ jobs:
           "sha256=$sha256Hash" >> $env:GITHUB_OUTPUT
           "exe_sha256=$exeSha256Hash" >> $env:GITHUB_OUTPUT
 
+      # Verified against the STAGING copy -- the exact bytes that ship. The invariant is "every
+      # AutopilotMonitor PE in the ZIP is signed", so a project added later cannot ride along
+      # unsigned. A missing timestamp fails too: without it the signature dies with the cert.
+      - name: Verify Authenticode signatures
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $files = Get-ChildItem -Path "staging/agent/*" -Include 'AutopilotMonitor.*.exe', 'AutopilotMonitor.*.dll' -File
+          if ($files.Count -lt 2) {
+            throw "Expected signed binaries in staging/agent, found $($files.Count)."
+          }
+
+          $failed = $false
+          $thumbprints = @{}
+          foreach ($file in $files) {
+            $sig = Get-AuthenticodeSignature -FilePath $file.FullName
+            if ($sig.Status -ne 'Valid') {
+              Write-Host "::error file=$($file.Name)::Signature status is '$($sig.Status)' -- expected 'Valid'."
+              $failed = $true
+              continue
+            }
+            if (-not $sig.TimeStamperCertificate) {
+              Write-Host "::error file=$($file.Name)::Signature carries no RFC-3161 timestamp -- it would expire with the certificate."
+              $failed = $true
+              continue
+            }
+            if (-not [string]::IsNullOrWhiteSpace($env:CODE_SIGN_EXPECTED_SUBJECT) -and
+                $sig.SignerCertificate.Subject -notlike $env:CODE_SIGN_EXPECTED_SUBJECT) {
+              Write-Host "::error file=$($file.Name)::Signed by '$($sig.SignerCertificate.Subject)', expected '$env:CODE_SIGN_EXPECTED_SUBJECT'."
+              $failed = $true
+              continue
+            }
+            $thumbprints[$sig.SignerCertificate.Thumbprint] = $true
+            Write-Host "$($file.Name): Valid, timestamped $($sig.TimeStamperCertificate.Subject.Split(',')[0]), signer $($sig.SignerCertificate.Subject)"
+          }
+
+          if ($thumbprints.Count -gt 1) {
+            Write-Host "::error::Staged binaries carry $($thumbprints.Count) different signing certificates -- expected exactly one."
+            $failed = $true
+          }
+          if ($failed) {
+            throw "Signature verification failed. Nothing was published."
+          }
+          Write-Host "All $($files.Count) binaries signed with certificate $($thumbprints.Keys -join ', ')"
+
       - name: Upload to Azure Blob Storage
         if: inputs.upload_blob
         shell: pwsh
         run: |
           $containerUrl = "https://autopilotmonitoreu.blob.core.windows.net/agent"
-          $sasToken = "${{ secrets.AZURE_BLOB_AGENT_SAS_TOKEN }}".TrimStart('?')
+          $authHeaders = & ./.github/scripts/Get-StorageAuthHeaders.ps1
           # Legacy mirror (transition until customers moved to the download.-alias):
           # blobs are ALSO pushed to the old account so the bootstrap URL baked into
           # customers' Intune scripts keeps serving current bits. Fail-soft -- a
@@ -234,7 +380,6 @@ jobs:
 
           function Send-Blob {
             param([string]$Local, [string]$BlobName, [string]$ContentType)
-            $url = "$containerUrl/$BlobName`?$sasToken"
             $bytes = [System.IO.File]::ReadAllBytes($Local)
             # no-cache on EVERY blob: they all rotate in place (even the per-line ZIP is
             # overwritten each build), and the download alias fronts them with Front Door.
@@ -248,7 +393,7 @@ jobs:
               $md5.Dispose()
             }
             Write-Host "Uploading $BlobName ($([math]::Round($bytes.Length / 1MB, 2)) MB)..."
-            Invoke-RestMethod -Uri $url -Method Put -Headers $headers -Body $bytes
+            Invoke-RestMethod -Uri "$containerUrl/$BlobName" -Method Put -Headers ($authHeaders + $headers) -Body $bytes
             Write-Host "  uploaded $BlobName"
             if (-not [string]::IsNullOrEmpty($legacySasToken)) {
               try {
@@ -274,56 +419,66 @@ jobs:
             # to main, so a release lands a set that is consistent with what is already live
             # (dev render, version-bump guard, bootstrapVersion oracles, alias verification).
             # Runs AFTER version.json so its bootstrapVersion read sees this build's manifest.
+            # Signed with the same identity: the device-side loader verifies the publisher
+            # of what it downloads, and the publisher refuses to upload unsigned scripts.
             ./.github/scripts/Publish-BootstrapScripts.ps1 `
-              -SasToken '${{ secrets.AZURE_BLOB_AGENT_SAS_TOKEN }}' `
               -LegacySasToken '${{ secrets.AZURE_BLOB_AGENT_LEGACY_SAS_TOKEN }}' `
-              -TableSasToken '${{ secrets.AZURE_TABLE_ADMIN_SAS_TOKEN }}'
+              -SigningToken $env:CODE_SIGN_AKV_ACCESS_TOKEN `
+              -KeyVaultUrl $env:CODE_SIGN_KEY_VAULT_URL `
+              -CertificateName $env:CODE_SIGN_CERTIFICATE_NAME `
+              -TimestampUrl $env:CODE_SIGN_TIMESTAMP_URL `
+              -ExpectedPublisher $env:CODE_SIGN_EXPECTED_SUBJECT
           }
 
           # Update AdminConfiguration LatestAgentV2* -- ONLY on stable cutover. The hash-oracle
           # must never point at a build that is not actually in the stable namespace.
           # LatestBootstrapV2ScriptVersion is NOT set here: it belongs to the script publisher
           # above, which also owns it on script-only pushes. One writer per field.
-          $tableSasToken = "${{ secrets.AZURE_TABLE_ADMIN_SAS_TOKEN }}".TrimStart('?')
           if ('${{ inputs.publish_as_stable }}' -ne 'true') {
             Write-Host "SKIPPED: AdminConfiguration update (versioned-only run -- stable namespace unchanged)"
-          } elseif ([string]::IsNullOrEmpty($tableSasToken) -or $tableSasToken -eq "XXX") {
-            Write-Host "SKIPPED: Table SAS token not configured -- set AZURE_TABLE_ADMIN_SAS_TOKEN secret to enable backend hash-oracle"
           } else {
             $sha256 = "${{ steps.artifact.outputs.sha256 }}"
             $exeSha256 = "${{ steps.artifact.outputs.exe_sha256 }}"
             $agentVersion = "${{ steps.version.outputs.version }}"
-            $tableUrl = "https://autopilotmonitoreu.table.core.windows.net/AdminConfiguration(PartitionKey='GlobalConfig',RowKey='config')?$tableSasToken"
+            $tableUrl = "https://autopilotmonitoreu.table.core.windows.net/AdminConfiguration(PartitionKey='GlobalConfig',RowKey='config')"
             $tableBody = @{
               LatestAgentV2Version    = $agentVersion
               LatestAgentV2Sha256     = $sha256
               LatestAgentV2ExeSha256  = $exeSha256
             }
-            Invoke-RestMethod -Uri $tableUrl -Method Merge -Headers @{
+            Invoke-RestMethod -Uri $tableUrl -Method Merge -Headers ($authHeaders + @{
               "Content-Type" = "application/json"
               "Accept"       = "application/json;odata=nometadata"
               "If-Match"     = "*"
-            } -Body ($tableBody | ConvertTo-Json)
+            }) -Body ($tableBody | ConvertTo-Json)
             Write-Host "AdminConfiguration updated: V2 version=$agentVersion, sha256=$sha256, exeSha256=$exeSha256"
           }
 
-      # Sigstore keyless provenance: binds the ZIP digest to this workflow run (repo, ref,
-      # commit, workflow file) in a public transparency log. The digest covers the identical
+      # Sigstore keyless provenance: binds the artifact digests to this workflow run (repo, ref,
+      # commit, workflow file) in a public transparency log. The digests cover the identical
       # bytes uploaded to blob (versioned AND stable), so one attestation covers all copies.
-      # Verify: gh attestation verify <zip> --repo okieselbach/AutopilotMonitor
-      - name: Attest build provenance (ZIP)
-        uses: actions/attest-build-provenance@v4
+      # Complements Authenticode rather than replacing it: the signature says who published a
+      # binary, the attestation which build produced these exact bytes. Both EXEs are subjects
+      # of their own so an extracted binary can be verified without the ZIP.
+      # Verify: gh attestation verify <file> --repo okieselbach/AutopilotMonitor
+      # Skipped on runs that publish nothing -- no log entry for bytes nobody receives.
+      - name: Attest build provenance
+        if: inputs.upload_blob || inputs.create_release
+        uses: actions/attest-build-provenance@4d101475d8b20a2381f78447822ac1eab6504dd8 # v4.2.2
         with:
-          subject-path: ${{ steps.artifact.outputs.versioned_zip_release }}
+          subject-path: |
+            ${{ steps.artifact.outputs.versioned_zip_release }}
+            staging/agent/AutopilotMonitor.Agent.exe
+            staging/agent/AutopilotMonitor.SummaryDialog.exe
 
       - name: Upload build artifact
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: AutopilotMonitor-Agent-v${{ steps.version.outputs.version }}
           path: ${{ steps.artifact.outputs.versioned_zip_release }}
 
       - name: Upload version metadata
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: version-metadata
           path: ${{ env.MANIFEST_NAME }}
@@ -356,7 +511,7 @@ jobs:
             - **Published as stable:** ${{ inputs.publish_as_stable }}
 
             ### Provenance
-            This ZIP carries a [GitHub Artifact Attestation](https://github.com/okieselbach/AutopilotMonitor/attestations) (Sigstore keyless). Verify:
+            The executables are Authenticode-signed and timestamped. The ZIP and both executables carry a [GitHub Artifact Attestation](https://github.com/okieselbach/AutopilotMonitor/attestations) (Sigstore keyless). Verify:
             ```
             gh attestation verify AutopilotMonitor-Agent-v${{ steps.version.outputs.version }}.zip --repo okieselbach/AutopilotMonitor
             ```

.github/workflows/build-msi.yml

@@ -1,11 +1,11 @@
 name: Build & Publish Bootstrap MSI
 
 # Thin MDM LOB delivery vehicle for WDP (Autopilot v2) — see
-# src/Agent/AutopilotMonitor.BootstrapMsi/Package.wxs. The MSI carries no bootstrap
-# logic (only the runner script that downloads the CURRENT server-hosted
-# Install-AutopilotMonitor.ps1), so it is rebuilt rarely: only when the runner script
-# or the WiX package changes. Version lives in Package.wxs — bump it there before
-# dispatching so Intune LOB update detection sees a new ProductVersion.
+# src/Agent/AutopilotMonitor.BootstrapMsi/Package.wxs. The MSI is packaging only: it
+# carries the SAME stage-1 loader that is assigned directly in Intune, so it is rebuilt
+# rarely — only when that loader or the WiX package changes. Version lives in Package.wxs
+# — bump it there before dispatching so Intune LOB update detection sees a new
+# ProductVersion.
 
 on:
   workflow_dispatch:
@@ -23,8 +23,15 @@ permissions:
 
 env:
   MSI_PROJECT_DIR: src/Agent/AutopilotMonitor.BootstrapMsi
-  RUNNER_SCRIPT: src/Agent/AutopilotMonitor.BootstrapMsi/Invoke-BootstrapDownload.ps1
+  RUNNER_SCRIPT: scripts/Bootstrap/Start-AutopilotMonitor.ps1
   STABLE_MSI: AutopilotMonitor-Bootstrap.msi
+  # Authenticode via Azure Key Vault; identity and vault come from repository variables.
+  # CODE_SIGN_EXPECTED_SUBJECT is optional and pins the publisher in the verify steps.
+  CODE_SIGN_CLIENT_ID: ${{ vars.CODE_SIGN_CLIENT_ID }}
+  CODE_SIGN_CERTIFICATE_NAME: ${{ vars.CODE_SIGN_CERTIFICATE_NAME }}
+  CODE_SIGN_KEY_VAULT_URL: ${{ vars.CODE_SIGN_KEY_VAULT_URL }}
+  CODE_SIGN_EXPECTED_SUBJECT: ${{ vars.CODE_SIGN_EXPECTED_SUBJECT }}
+  CODE_SIGN_TIMESTAMP_URL: http://timestamp.acs.microsoft.com
 
 jobs:
   build:
@@ -33,10 +40,14 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      # The runner executes as SYSTEM on every enrolling device — a parse error or
+      # The loader executes as SYSTEM on every enrolling device — a parse error or
       # non-ASCII mojibake (PS 5.1 codepage roulette) must fail the build, not the fleet.
+      # bootstrap-script-gates.yml runs the same checks plus Pester on pushes; this job
+      # stands on its own because it can be dispatched at any time.
       - name: Validate runner script (parse + ASCII-only)
         shell: pwsh
         run: |
@@ -62,8 +73,77 @@ jobs:
           Write-Host "MSI version (from Package.wxs): $version"
           "version=$version" >> $env:GITHUB_OUTPUT
 
+      # Every published MSI is signed; a missing variable stops the run before the build.
+      - name: Check code-signing configuration
+        shell: pwsh
+        run: |
+          foreach ($name in 'CODE_SIGN_CLIENT_ID', 'CODE_SIGN_CERTIFICATE_NAME', 'CODE_SIGN_KEY_VAULT_URL') {
+            if ([string]::IsNullOrWhiteSpace([Environment]::GetEnvironmentVariable($name))) {
+              throw "Repository variable $name is not set. Every published MSI must be Authenticode-signed."
+            }
+          }
+
+      # Logs in FIRST and only to fetch the Key Vault token: azure/login sets the default az
+      # account, so the storage login below has to be the last one. Both federated credentials
+      # are bound to the ref, so this job must never be given an `environment:` -- that would
+      # change the OIDC subject claim and break both logins.
+      - name: Login to Azure (code-signing identity)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ env.CODE_SIGN_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          allow-no-subscriptions: true
+
+      - name: Acquire Key Vault token for signing
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $token = az account get-access-token --scope https://vault.azure.net/.default --query accessToken --output tsv
+          if ($LASTEXITCODE -ne 0 -or [string]::IsNullOrWhiteSpace($token)) {
+            throw "Could not acquire a Key Vault token for the code-signing identity."
+          }
+          Write-Host "::add-mask::$token"
+          "CODE_SIGN_AKV_ACCESS_TOKEN=$token" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+
+      # The blob upload below is authorized by this federated identity, not by a SAS.
+      - name: Login to Azure (OIDC)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+
+      # Exact version, not a "5.*" range: wix writes the bytes of the MSI that customers
+      # install, so a compromised or simply broken point release must not flow into a build
+      # unnoticed. Bumping is a reviewed commit.
       - name: Install WiX toolset
-        run: dotnet tool install --global wix --version "5.*"
+        run: dotnet tool install --global wix --version 5.0.2
+
+      # Version pinned; roll-forward because the tool targets an older runtime than the SDK.
+      - name: Install AzureSignTool
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
+        run: dotnet tool install --no-cache --global AzureSignTool --version 7.0.1
+
+      # BEFORE the build: wix embeds the file as it finds it, so a loader signed afterwards
+      # would leave the copy inside the MSI unsigned. Devices under an AllSigned policy need
+      # the embedded loader to carry a signature of its own.
+      - name: Sign bootstrap loader (Authenticode)
+        shell: pwsh
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
+        run: |
+          $ErrorActionPreference = 'Stop'
+          & azuresigntool.exe sign --verbose `
+            --azure-key-vault-url "$env:CODE_SIGN_KEY_VAULT_URL" `
+            --azure-key-vault-accesstoken "$env:CODE_SIGN_AKV_ACCESS_TOKEN" `
+            --azure-key-vault-certificate "$env:CODE_SIGN_CERTIFICATE_NAME" `
+            --timestamp-rfc3161 "$env:CODE_SIGN_TIMESTAMP_URL" `
+            --file-digest sha256 `
+            --description 'Autopilot Monitor bootstrap runner' `
+            --description-url 'https://www.autopilotmonitor.com' `
+            $env:RUNNER_SCRIPT
+          if ($LASTEXITCODE -ne 0) { throw "azuresigntool failed with exit code $LASTEXITCODE" }
 
       - name: Build MSI
         shell: pwsh
@@ -75,16 +155,46 @@ jobs:
           wix build Package.wxs -arch x64 -o $out
           Pop-Location
           if (-not (Test-Path $env:STABLE_MSI)) { Write-Error "wix build produced no MSI"; exit 1 }
-          $sha256 = (Get-FileHash $env:STABLE_MSI -Algorithm SHA256).Hash.ToLowerInvariant()
           Write-Host "Built $env:STABLE_MSI ($([math]::Round((Get-Item $env:STABLE_MSI).Length / 1KB)) KB)"
-          Write-Host "SHA-256: $sha256"
+
+      # Signing rewrites the MSI, so it runs before the hash and the upload. A missing
+      # timestamp fails the run: without it the signature dies with the certificate.
+      - name: Sign MSI (Authenticode)
+        shell: pwsh
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
+        run: |
+          $ErrorActionPreference = 'Stop'
+          & azuresigntool.exe sign --verbose `
+            --azure-key-vault-url "$env:CODE_SIGN_KEY_VAULT_URL" `
+            --azure-key-vault-accesstoken "$env:CODE_SIGN_AKV_ACCESS_TOKEN" `
+            --azure-key-vault-certificate "$env:CODE_SIGN_CERTIFICATE_NAME" `
+            --timestamp-rfc3161 "$env:CODE_SIGN_TIMESTAMP_URL" `
+            --file-digest sha256 `
+            --description 'Autopilot Monitor Bootstrap' `
+            --description-url 'https://www.autopilotmonitor.com' `
+            $env:STABLE_MSI
+          if ($LASTEXITCODE -ne 0) { throw "azuresigntool failed with exit code $LASTEXITCODE" }
+
+          # The MSI and the loader it carries -- verified here, before anything is published.
+          foreach ($file in @($env:STABLE_MSI, $env:RUNNER_SCRIPT)) {
+            $sig = Get-AuthenticodeSignature -FilePath $file
+            if ($sig.Status -ne 'Valid') { throw "Signature on $file is '$($sig.Status)', expected 'Valid'." }
+            if (-not $sig.TimeStamperCertificate) { throw "Signature on $file carries no timestamp." }
+            if ($env:CODE_SIGN_EXPECTED_SUBJECT -and $sig.SignerCertificate.Subject -notlike $env:CODE_SIGN_EXPECTED_SUBJECT) {
+              throw "$file was signed by '$($sig.SignerCertificate.Subject)', expected '$env:CODE_SIGN_EXPECTED_SUBJECT'."
+            }
+            Write-Host "$file : Valid, timestamped, signer $($sig.SignerCertificate.Subject.Split(',')[0])"
+          }
+
+          Write-Host "SHA-256: $((Get-FileHash $env:STABLE_MSI -Algorithm SHA256).Hash.ToLowerInvariant())"
 
       - name: Upload to Azure Blob Storage
         if: inputs.upload_blob
         shell: pwsh
         run: |
           $containerUrl = "https://autopilotmonitoreu.blob.core.windows.net/agent"
-          $sasToken = "${{ secrets.AZURE_BLOB_AGENT_SAS_TOKEN }}".TrimStart('?')
+          $authHeaders = & ./.github/scripts/Get-StorageAuthHeaders.ps1
           $version = "${{ steps.version.outputs.version }}"
 
           # Same Send-Blob contract as build-agent.yml: no-cache on every blob because the
@@ -102,7 +212,7 @@ jobs:
             $headers["Content-MD5"] = [Convert]::ToBase64String($md5.ComputeHash($bytes))
             $md5.Dispose()
             Write-Host "Uploading $BlobName ($([math]::Round($bytes.Length / 1KB)) KB)..."
-            Invoke-RestMethod -Uri "$containerUrl/$BlobName`?$sasToken" -Method Put -Headers $headers -Body $bytes
+            Invoke-RestMethod -Uri "$containerUrl/$BlobName" -Method Put -Headers ($authHeaders + $headers) -Body $bytes
             Write-Host "  uploaded $BlobName"
           }
 
@@ -125,15 +235,17 @@ jobs:
           }
           Write-Host "Alias verified: https://download.autopilotmonitor.com/agent/$env:STABLE_MSI ($remoteSize bytes)"
 
-      # Sigstore keyless provenance, same as the agent ZIP. Verify:
+      # Sigstore keyless provenance, same as the agent ZIP; covers the signed bytes. Skipped
+      # on runs that publish nothing -- no log entry for bytes nobody receives. Verify:
       # gh attestation verify AutopilotMonitor-Bootstrap.msi --repo okieselbach/AutopilotMonitor
       - name: Attest build provenance (MSI)
-        uses: actions/attest-build-provenance@v4
+        if: inputs.upload_blob
+        uses: actions/attest-build-provenance@4d101475d8b20a2381f78447822ac1eab6504dd8 # v4.2.2
         with:
           subject-path: ${{ env.STABLE_MSI }}
 
       - name: Upload build artifact
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: AutopilotMonitor-Bootstrap-v${{ steps.version.outputs.version }}
           path: ${{ env.STABLE_MSI }}

.github/workflows/ci.yml

@@ -24,6 +24,7 @@ on:
       - 'infra/**'
       - '.claude/**'
       - '.gitmodules'
+      - 'zizmor.yml'
       - '**/*.md'
       - 'LICENSE'
       - '.github/ISSUE_TEMPLATE/**'
@@ -35,6 +36,7 @@ on:
       # Every other workflow: nothing here builds or tests anything CI covers. paths-ignore
       # cannot negate, so they are listed one by one; ci.yml itself stays out of the list
       # so a change to CI runs CI. A new workflow file is opt-in — add it here too.
+      - '.github/workflows/action-pins.yml'
       - '.github/workflows/bootstrap-script-gates.yml'
       - '.github/workflows/build-agent.yml'
       - '.github/workflows/build-msi.yml'
@@ -56,6 +58,7 @@ on:
       - 'infra/**'
       - '.claude/**'
       - '.gitmodules'
+      - 'zizmor.yml'
       - '**/*.md'
       - 'LICENSE'
       - '.github/ISSUE_TEMPLATE/**'
@@ -67,6 +70,7 @@ on:
       # Every other workflow: nothing here builds or tests anything CI covers. paths-ignore
       # cannot negate, so they are listed one by one; ci.yml itself stays out of the list
       # so a change to CI runs CI. A new workflow file is opt-in — add it here too.
+      - '.github/workflows/action-pins.yml'
       - '.github/workflows/bootstrap-script-gates.yml'
       - '.github/workflows/build-agent.yml'
       - '.github/workflows/build-msi.yml'
@@ -94,9 +98,11 @@ jobs:
     # windows-latest is required: the agent test projects target net48.
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      - uses: actions/setup-dotnet@v6
+      - uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
         with:
           dotnet-version: '10.0.x'
 
@@ -118,6 +124,9 @@ jobs:
       - name: Summary Dialog tests
         run: dotnet test src/Agent/AutopilotMonitor.SummaryDialog.Tests --configuration Release --no-build --verbosity quiet --logger "console;verbosity=minimal"
 
+      - name: Push tests
+        run: dotnet test src/Push/AutopilotMonitor.Push.Tests --configuration Release --no-build --verbosity quiet --logger "console;verbosity=minimal"
+
   web:
     name: Web (typecheck + tests)
     runs-on: ubuntu-latest
@@ -125,9 +134,11 @@ jobs:
       run:
         working-directory: src/Web/autopilot-monitor-web
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: '22'
           cache: npm
@@ -159,9 +170,11 @@ jobs:
       run:
         working-directory: src/McpServer/autopilot-monitor-mcp
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: '22'
           cache: npm
@@ -179,7 +192,7 @@ jobs:
       # (run 31252869254). Persist the model across runs instead; HF_CACHE_DIR
       # is honored by vector-search-provider.ts.
       - name: Cache embedding model
-        uses: actions/cache@v6
+        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:
           path: ${{ github.workspace }}/.hf-cache
           key: hf-model-Xenova-all-MiniLM-L6-v2
@@ -193,9 +206,11 @@ jobs:
     name: Generated guardrails match rules/guardrails.json
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: '22'
 
@@ -214,9 +229,11 @@ jobs:
     name: Generated wire types match shared-manifests.json
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: '22'
 

.github/workflows/codeql.yml

@@ -17,6 +17,7 @@ on:
       - 'infra/**'
       - '.claude/**'
       - '.gitmodules'
+      - 'zizmor.yml'
       - '**/*.md'
       - 'LICENSE'
       - '.github/ISSUE_TEMPLATE/**'
@@ -48,6 +49,7 @@ on:
       - 'infra/**'
       - '.claude/**'
       - '.gitmodules'
+      - 'zizmor.yml'
       - '**/*.md'
       - 'LICENSE'
       - '.github/ISSUE_TEMPLATE/**'
@@ -102,15 +104,17 @@ jobs:
             build-mode: none
 
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
-      - uses: actions/setup-dotnet@v6
+      - uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
         if: matrix.language == 'csharp'
         with:
           dotnet-version: '10.0.x'
 
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@v4.37.9
+        uses: github/codeql-action/init@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
         with:
           languages: ${{ matrix.language }}
           build-mode: ${{ matrix.build-mode }}
@@ -121,6 +125,6 @@ jobs:
         run: dotnet build AutopilotMonitor.sln --configuration Release
 
       - name: Analyze
-        uses: github/codeql-action/analyze@v4.37.9
+        uses: github/codeql-action/analyze@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
         with:
           category: /language:${{ matrix.language }}

.github/workflows/combine-rules.yml

@@ -24,41 +24,26 @@ jobs:
     permissions:
       contents: write
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
-      - uses: actions/setup-node@v7
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: '22'
 
-      - name: Install ajv-cli
-        run: npm install -g ajv-cli ajv-formats
+      # Lockfile and no lifecycle scripts: this job holds contents:write and pushes to
+      # main, so an install-time script from a hijacked package would run with a token that
+      # can rewrite the repository. rules/scripts/package-lock.json pins ajv, ajv-formats
+      # and every transitive package (Dependabot keeps it current); ajv is pure JS and
+      # needs no install hooks.
+      - name: Install the rules validator from the lockfile
+        working-directory: rules/scripts
+        run: npm ci --ignore-scripts
 
-      - name: Validate Gather Rules
-        run: |
-          for f in rules/gather/*.json; do
-            echo "Validating $f..."
-            ajv validate -s rules/schema/gather-rule.schema.json -d "$f" --spec=draft2020 -c ajv-formats
-          done
-
-      - name: Validate Analyze Rules
-        run: |
-          for f in rules/analyze/*.json; do
-            echo "Validating $f..."
-            ajv validate -s rules/schema/analyze-rule.schema.json -d "$f" --spec=draft2020 -c ajv-formats
-          done
-
-      - name: Validate IME Log Patterns
-        run: |
-          for f in rules/ime-log-patterns/*.json; do
-            echo "Validating $f..."
-            ajv validate -s rules/schema/ime-log-pattern.schema.json -d "$f" --spec=draft2020 -c ajv-formats
-          done
-
-      # guardrails.json values are baked verbatim into generated TypeScript that is
-      # auto-committed to main and shipped to the portal - the schema forbids control
-      # and line-terminator characters so a "data" PR can never become code.
-      - name: Validate Guardrails
-        run: ajv validate -s rules/schema/guardrails.schema.json -d rules/guardrails.json --spec=draft2020 -c ajv-formats
+      # Gather, analyze and IME log pattern files plus guardrails.json, each against its
+      # schema; the guardrails schema is what keeps a "data" PR from becoming code in the
+      # generated TypeScript (see validate.js).
+      - name: Validate rules and guardrails against their schemas
+        run: node rules/scripts/validate.js
 
       - name: Combine rules into dist/
         run: node rules/scripts/combine.js

.github/workflows/deploy-backend.yml

@@ -19,17 +19,19 @@ jobs:
     name: Build and Deploy Backend
 
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
       - name: Login to Azure (OIDC)
-        uses: azure/login@7ddb5af1ef8758cf1353cf3b42f940aee27ba21c # v3
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
         with:
           client-id: ${{ secrets.AZURE_CLIENT_ID }}
           tenant-id: ${{ secrets.AZURE_TENANT_ID }}
           subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
 
       - name: Setup .NET 10
-        uses: actions/setup-dotnet@v6
+        uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
         with:
           dotnet-version: '10.0.x'
 
@@ -41,7 +43,7 @@ jobs:
         id: version
         shell: pwsh
         run: |
-          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl "${{ env.VERSIONS_CONTAINER }}/backend.txt" -SasToken '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'
+          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl "${{ env.VERSIONS_CONTAINER }}/backend.txt"
 
           $csproj = Get-Content ${{ env.CSPROJ_PATH }} -Raw
           if ($csproj -notmatch '<VersionPrefix>(\d+\.\d+)</VersionPrefix>') {
@@ -65,7 +67,7 @@ jobs:
         run: dotnet publish ${{ env.CSPROJ_PATH }} --configuration Release --output ./publish --no-build -p:SourceRevisionId=${{ github.sha }} -p:BuildNumber=${{ steps.version.outputs.build_number }} -p:BuildTimestampUtc=${{ steps.version.outputs.build_utc }}
 
       - name: Deploy to Azure Functions
-        uses: Azure/functions-action@c5060b3b8bb1ebbcb531abd00c822ecbaa8ea656 # v1
+        uses: Azure/functions-action@c5060b3b8bb1ebbcb531abd00c822ecbaa8ea656 # v1.5.7
         with:
           app-name: ${{ env.FUNCTION_APP }}
           package: ./publish
@@ -115,9 +117,9 @@ jobs:
             runId       = '${{ github.run_id }}'
           } | ConvertTo-Json
 
-          $sas = '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'.TrimStart('?')
-          $url = "${{ env.VERSIONS_CONTAINER }}/backend.json?$sas"
+          $authHeaders = & ./.github/scripts/Get-StorageAuthHeaders.ps1
+          $url = "${{ env.VERSIONS_CONTAINER }}/backend.json"
           # no-cache: rotating pointer, must never be served stale by any fronting cache.
-          Invoke-RestMethod -Uri $url -Method Put -Headers @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' } -Body $manifest -ContentType 'application/json' | Out-Null
+          Invoke-RestMethod -Uri $url -Method Put -Headers ($authHeaders + @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' }) -Body $manifest -ContentType 'application/json' | Out-Null
           Write-Host "Published versions/backend.json"
           Write-Host $manifest

.github/workflows/deploy-mcp.yml

@@ -26,7 +26,9 @@ jobs:
     name: Build and Deploy MCP Server
 
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
       # The published customer documentation lives in its own PUBLIC repo and is
       # baked into the image as the search_docs corpus (see the Dockerfile). No
@@ -36,8 +38,9 @@ jobs:
       # re-run actually rolls a new revision). /health reports the SHA captured
       # below so that staleness is checkable.
       - name: Check out documentation bundle
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
+          persist-credentials: false
           repository: autopilotmonitor/autopilotmonitor-docs
           path: mcp-docs
 
@@ -46,7 +49,7 @@ jobs:
         run: echo "sha=$(git -C mcp-docs rev-parse HEAD)" >> "$GITHUB_OUTPUT"
 
       - name: Login to Azure (OIDC)
-        uses: azure/login@7ddb5af1ef8758cf1353cf3b42f940aee27ba21c # v3
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
         with:
           client-id: ${{ secrets.AZURE_CLIENT_ID }}
           tenant-id: ${{ secrets.AZURE_TENANT_ID }}
@@ -59,7 +62,7 @@ jobs:
         id: version
         shell: pwsh
         run: |
-          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl "${{ env.VERSIONS_CONTAINER }}/mcp.txt" -SasToken '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'
+          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl "${{ env.VERSIONS_CONTAINER }}/mcp.txt"
 
           $pkgVersion = (Get-Content ${{ env.PACKAGE_JSON }} -Raw | ConvertFrom-Json).version
           $prefix = ($pkgVersion -split '\.')[0..1] -join '.'
@@ -77,7 +80,7 @@ jobs:
           "short_sha=$shortSha" >> $env:GITHUB_OUTPUT
 
       - name: Login to ACR
-        run: az acr login --name ${{ env.ACR_NAME }}
+        run: az acr login --name "$ACR_NAME"
 
       - name: Build and push container image
         run: |
@@ -87,17 +90,17 @@ jobs:
             --build-arg BUILD_NUMBER=${{ steps.version.outputs.build_number }} \
             --build-arg BUILD_COMMIT=${{ steps.version.outputs.short_sha }} \
             --build-arg BUILD_UTC=${{ steps.version.outputs.build_utc }} \
-            -t ${{ env.ACR_NAME }}.azurecr.io/${{ env.CONTAINER_APP_NAME }}:${{ env.IMAGE_TAG }} \
-            -t ${{ env.ACR_NAME }}.azurecr.io/${{ env.CONTAINER_APP_NAME }}:latest \
+            -t "$ACR_NAME.azurecr.io/$CONTAINER_APP_NAME:$IMAGE_TAG" \
+            -t "$ACR_NAME.azurecr.io/$CONTAINER_APP_NAME:latest" \
             .
-          docker push ${{ env.ACR_NAME }}.azurecr.io/${{ env.CONTAINER_APP_NAME }} --all-tags
+          docker push "$ACR_NAME.azurecr.io/$CONTAINER_APP_NAME" --all-tags
 
       - name: Deploy to Container App
         run: |
           az containerapp update \
-            --name ${{ env.CONTAINER_APP_NAME }} \
-            --resource-group ${{ env.RESOURCE_GROUP }} \
-            --image ${{ env.ACR_NAME }}.azurecr.io/${{ env.CONTAINER_APP_NAME }}:${{ env.IMAGE_TAG }}
+            --name "$CONTAINER_APP_NAME" \
+            --resource-group "$RESOURCE_GROUP" \
+            --image "$ACR_NAME.azurecr.io/$CONTAINER_APP_NAME:$IMAGE_TAG"
 
       # `az containerapp update` returns once the revision is provisioned, not once
       # it serves traffic — and with minReplicas=0 the first request also pays a cold
@@ -144,9 +147,9 @@ jobs:
             docsCommit  = '${{ steps.docs.outputs.sha }}'.Substring(0, 7)
           } | ConvertTo-Json
 
-          $sas = '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'.TrimStart('?')
-          $url = "${{ env.VERSIONS_CONTAINER }}/mcp.json?$sas"
+          $authHeaders = & ./.github/scripts/Get-StorageAuthHeaders.ps1
+          $url = "${{ env.VERSIONS_CONTAINER }}/mcp.json"
           # no-cache: rotating pointer, must never be served stale by any fronting cache.
-          Invoke-RestMethod -Uri $url -Method Put -Headers @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' } -Body $manifest -ContentType 'application/json' | Out-Null
+          Invoke-RestMethod -Uri $url -Method Put -Headers ($authHeaders + @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' }) -Body $manifest -ContentType 'application/json' | Out-Null
           Write-Host "Published versions/mcp.json"
           Write-Host $manifest

.github/workflows/deploy-web.yml

@@ -35,12 +35,40 @@ jobs:
     runs-on: ubuntu-latest
     name: Build and Deploy Job
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
+          persist-credentials: false
           lfs: false
           fetch-depth: 0  # Full history needed for git-based sitemap lastmod dates
 
-      - uses: actions/setup-node@v7
+      # Only the version manifest at the very end needs Azure; logging in here rather than
+      # next to that step keeps a credential problem from surfacing after a live deploy.
+      - name: Login to Azure (OIDC)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+
+      # The customer docs repo is the single source of the "What's new" panel: the prebuild
+      # step (scripts/whats-new/build-whats-new.js) turns changelog/*.md into
+      # public/whats-new.json and dates every bullet via git blame — hence the full history.
+      # Public repo, no token. Editing the docs does NOT update the live panel until this
+      # workflow runs again (push under src/Web/** or a manual dispatch); versions/web.json
+      # records which docs commit is live.
+      - name: Check out documentation bundle
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+          repository: autopilotmonitor/autopilotmonitor-docs
+          path: whats-new-docs
+          fetch-depth: 0
+
+      - name: Resolve docs commit
+        id: docs
+        run: echo "sha=$(git -C whats-new-docs rev-parse HEAD)" >> "$GITHUB_OUTPUT"
+
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: '22'
           cache: npm
@@ -50,8 +78,25 @@ jobs:
         working-directory: ${{ env.WEB_DIR }}
         run: npm ci
 
+      # Star counter for the GitHub star link (utils/githubStars.ts). Baked into the static HTML
+      # so visitors' browsers never call GitHub; stale until the next web deploy. The token stays
+      # in this step, never in the build. Fail-soft: without a number the link has no counter.
+      - name: Read GitHub star count (fail-soft)
+        id: stars
+        env:
+          GH_TOKEN: ${{ github.token }}
+          REPO: ${{ github.repository }}
+        run: |
+          count=$(gh api "repos/$REPO" --jq .stargazers_count 2>/dev/null || true)
+          if [[ "$count" =~ ^[0-9]+$ ]]; then
+            echo "count=$count" >> "$GITHUB_OUTPUT"
+            echo "GitHub stars: $count"
+          else
+            echo "::warning::GitHub star count unavailable - the star link renders without a counter"
+          fi
+
       # next.config output:'export' -- `next build` writes the static site to out/
-      # (prebuild: sync-error-codes, generate-lastmod, generate-version).
+      # (prebuild: sync-error-codes, generate-lastmod, generate-version, whats-new).
       - name: Build
         working-directory: ${{ env.WEB_DIR }}
         env:
@@ -63,14 +108,24 @@ jobs:
           NEXT_PUBLIC_ENTRA_REDIRECT_URI: ${{ vars.NEXT_PUBLIC_ENTRA_REDIRECT_URI }}
           NEXT_PUBLIC_ENTRA_POST_LOGOUT_REDIRECT_URI: ${{ vars.NEXT_PUBLIC_ENTRA_POST_LOGOUT_REDIRECT_URI }}
           NEXT_PUBLIC_API_BASE_URL: ${{ vars.NEXT_PUBLIC_API_BASE_URL }}
+          # Browsers load the live stats through it, and the build reads it once to bake the
+          # numbers of this moment into the landing page's static HTML (lib/platformStats.ts).
           NEXT_PUBLIC_PLATFORM_STATS_MANIFEST_URL: ${{ vars.NEXT_PUBLIC_PLATFORM_STATS_MANIFEST_URL }}
           NEXT_PUBLIC_APPINSIGHTS_CONNECTION_STRING: ${{ secrets.NEXT_PUBLIC_APPINSIGHTS_CONNECTION_STRING }}
           # Build stamp for public/version.json (scripts/generate-version.js in prebuild);
           # the verify step below polls the deployed file for exactly this commit.
           GITHUB_SHA: ${{ github.sha }}
+          # Docs checkout for public/whats-new.json; the prebuild fails in CI without it.
+          WHATS_NEW_DOCS_DIR: ${{ github.workspace }}/whats-new-docs
+          # Star counter from the step above; empty when the lookup failed.
+          NEXT_PUBLIC_GITHUB_STARS: ${{ steps.stars.outputs.count }}
         run: |
           npm run build
           test -f out/version.json || { echo "out/version.json missing - export did not run"; exit 1; }
+          test -f out/whats-new.json || { echo "out/whats-new.json missing - whats-new prebuild did not run"; exit 1; }
+          # Fail-soft like the star count: browsers still load the stats live; only crawlers and
+          # LLM fetchers, which run no JS, see no numbers until the next deploy.
+          grep -q 'data-stats-snapshot=' out/index.html || echo "::warning::Platform stats were not baked into the landing page (reason in the build log) - crawlers and LLM fetchers see no numbers until the next deploy"
 
       # One archive of the exact bytes that get uploaded, so the attestation has a single subject.
       - name: Package export
@@ -85,12 +140,12 @@ jobs:
       # commit, workflow file) in a public transparency log.
       # Verify: gh attestation verify portal-<sha>.tar.gz --repo okieselbach/AutopilotMonitor
       - name: Attest build provenance (portal export)
-        uses: actions/attest-build-provenance@v4
+        uses: actions/attest-build-provenance@4d101475d8b20a2381f78447822ac1eab6504dd8 # v4.2.2
         with:
           subject-path: ${{ steps.package.outputs.archive }}
 
       - name: Upload build artifact
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: portal-${{ github.sha }}
           path: ${{ steps.package.outputs.archive }}
@@ -136,7 +191,8 @@ jobs:
           throw "Portal did not serve commit $expectedCommit within 5 minutes -- deployment not verified, version manifest NOT published"
 
       # Cross-component deploy record, written last and only on a verified deploy --
-      # same contract as versions/backend.json and versions/mcp.json.
+      # same contract as versions/backend.json and versions/mcp.json. docsCommit says which
+      # docs revision the live What's new panel was generated from (as for the MCP corpus).
       - name: Publish version manifest
         shell: pwsh
         run: |
@@ -145,11 +201,12 @@ jobs:
             commit      = '${{ github.sha }}'.Substring(0, 7)
             deployedUtc = [DateTime]::UtcNow.ToString('o')
             runId       = '${{ github.run_id }}'
+            docsCommit  = '${{ steps.docs.outputs.sha }}'.Substring(0, 7)
           } | ConvertTo-Json
 
-          $sas = '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'.TrimStart('?')
-          $url = "${{ env.VERSIONS_CONTAINER }}/web.json?$sas"
+          $authHeaders = & ./.github/scripts/Get-StorageAuthHeaders.ps1
+          $url = "${{ env.VERSIONS_CONTAINER }}/web.json"
           # no-cache: rotating pointer, must never be served stale by any fronting cache.
-          Invoke-RestMethod -Uri $url -Method Put -Headers @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' } -Body $manifest -ContentType 'application/json' | Out-Null
+          Invoke-RestMethod -Uri $url -Method Put -Headers ($authHeaders + @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' }) -Body $manifest -ContentType 'application/json' | Out-Null
           Write-Host "Published versions/web.json"
           Write-Host $manifest

.github/workflows/indexnow-notify.yml

@@ -3,6 +3,9 @@ name: IndexNow Notify (Bing/Yandex)
 on:
   workflow_dispatch:
 
+# The job only talks to public endpoints; it never needs a repository token.
+permissions: {}
+
 jobs:
   notify:
     runs-on: ubuntu-latest

.github/workflows/oidc-login-test.yml

@@ -15,7 +15,7 @@ jobs:
     name: Federated login + read check
     steps:
       - name: Login to Azure (OIDC)
-        uses: azure/login@7ddb5af1ef8758cf1353cf3b42f940aee27ba21c # v3
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
         with:
           client-id: ${{ secrets.AZURE_CLIENT_ID }}
           tenant-id: ${{ secrets.AZURE_TENANT_ID }}

.github/workflows/pester.yml

@@ -25,5 +25,6 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
+  # $/ is the self-repository form: this repository at the running commit.
   gates:
-    uses: ./.github/workflows/bootstrap-script-gates.yml
+    uses: $/.github/workflows/bootstrap-script-gates.yml

.github/workflows/publish-scripts.yml

@@ -34,23 +34,109 @@ concurrency:
   group: agent-blob-publish
   cancel-in-progress: false
 
+# Authenticode for the customer scripts. Same identity and same repository variables as
+# build-agent.yml -- the loader on every device pins this publisher, so the two must not
+# drift apart.
+env:
+  CODE_SIGN_CLIENT_ID: ${{ vars.CODE_SIGN_CLIENT_ID }}
+  CODE_SIGN_CERTIFICATE_NAME: ${{ vars.CODE_SIGN_CERTIFICATE_NAME }}
+  CODE_SIGN_KEY_VAULT_URL: ${{ vars.CODE_SIGN_KEY_VAULT_URL }}
+  CODE_SIGN_EXPECTED_SUBJECT: ${{ vars.CODE_SIGN_EXPECTED_SUBJECT }}
+  CODE_SIGN_TIMESTAMP_URL: http://timestamp.acs.microsoft.com
+
 jobs:
+  # $/ is the self-repository form: this repository at the running commit, never a
+  # path some earlier step could have written to the workspace.
   gates:
-    uses: ./.github/workflows/bootstrap-script-gates.yml
+    uses: $/.github/workflows/bootstrap-script-gates.yml
 
   publish:
     name: Publish to the download alias
     needs: gates
     runs-on: windows-latest
+    # Job-scoped: only the publish job federates to Azure, the gates job never holds an
+    # OIDC token it does not need.
+    permissions:
+      contents: read
+      id-token: write   # OIDC federated login for the storage writes (secret-less)
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Check code-signing configuration
+        shell: pwsh
+        run: |
+          foreach ($name in 'CODE_SIGN_CLIENT_ID', 'CODE_SIGN_CERTIFICATE_NAME', 'CODE_SIGN_KEY_VAULT_URL') {
+            if ([string]::IsNullOrWhiteSpace([Environment]::GetEnvironmentVariable($name))) {
+              throw "Repository variable $name is not set. Published customer scripts must be signed."
+            }
+          }
+
+      # First, and only to fetch the Key Vault token: azure/login sets the default az
+      # account and the storage login below has to be the one that stays. See D-223 --
+      # both federated credentials are bound to the ref, so this job must never carry a
+      # GitHub `environment:`.
+      - name: Login to Azure (code-signing identity)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ env.CODE_SIGN_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          allow-no-subscriptions: true
+
+      - name: Acquire Key Vault token for signing
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $token = az account get-access-token --scope https://vault.azure.net/.default --query accessToken --output tsv
+          if ($LASTEXITCODE -ne 0 -or [string]::IsNullOrWhiteSpace($token)) {
+            throw "Could not acquire a Key Vault token for the code-signing identity."
+          }
+          Write-Host "::add-mask::$token"
+          "CODE_SIGN_AKV_ACCESS_TOKEN=$token" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+
+      # Authorizes the eu blob writes and the AdminConfiguration merge. The gates job above
+      # runs the same publisher with -DryRun and deliberately without a login -- a dry run
+      # must never need Azure credentials.
+      - name: Login to Azure (OIDC)
+        uses: azure/login@a641126d1b8aa4d1fa005f4f92df94a3a4c4c906 # v3.1.0
+        with:
+          client-id: ${{ secrets.AZURE_CLIENT_ID }}
+          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+
+      # Version pinned so a new or compromised NuGet release cannot flow into signing
+      # unreviewed; roll-forward because the tool targets an older runtime than the SDK
+      # preinstalled on the runner.
+      - name: Install AzureSignTool
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
+        run: dotnet tool install --no-cache --global AzureSignTool --version 7.0.1
 
       - name: Publish bootstrap + customer scripts
         shell: pwsh
+        env:
+          DOTNET_ROLL_FORWARD: LatestMajor
         run: |
           $dryRun = '${{ inputs.dry_run }}' -eq 'true'
           ./.github/scripts/Publish-BootstrapScripts.ps1 `
-            -SasToken '${{ secrets.AZURE_BLOB_AGENT_SAS_TOKEN }}' `
             -LegacySasToken '${{ secrets.AZURE_BLOB_AGENT_LEGACY_SAS_TOKEN }}' `
-            -TableSasToken '${{ secrets.AZURE_TABLE_ADMIN_SAS_TOKEN }}' `
+            -SigningToken $env:CODE_SIGN_AKV_ACCESS_TOKEN `
+            -KeyVaultUrl $env:CODE_SIGN_KEY_VAULT_URL `
+            -CertificateName $env:CODE_SIGN_CERTIFICATE_NAME `
+            -TimestampUrl $env:CODE_SIGN_TIMESTAMP_URL `
+            -ExpectedPublisher $env:CODE_SIGN_EXPECTED_SUBJECT `
+            -SignedOutputDir "$env:RUNNER_TEMP/signed-scripts" `
             -DryRun:$dryRun
+
+      # The exact bytes that were (or, on a dry run, would have been) uploaded. A dry-run
+      # dispatch is therefore the way to inspect a signed script locally before it reaches
+      # a single customer. Kept on failure too: a failed alias verification is precisely
+      # when someone wants to look at the file.
+      - name: Upload signed scripts
+        if: always()
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: signed-scripts
+          path: ${{ runner.temp }}/signed-scripts
+          if-no-files-found: ignore

.gitignore

@@ -145,6 +145,10 @@ internal/docs/~$Introduction-AutopilotMonitor.pptx
 # changes each run) and served at /version.json from the static export.
 src/Web/autopilot-monitor-web/public/version.json
 
+# What's new payload: generated by scripts/whats-new/build-whats-new.js from the docs
+# checkout on every build and served at /whats-new.json from the static export.
+src/Web/autopilot-monitor-web/public/whats-new.json
+
 
 # Local IME installer scratch (MSI + extracted payload per version, for grepping
 # in binaries). Operator-only, never committed.

AutopilotMonitor.sln

@@ -31,6 +31,12 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AutopilotMonitor.Agent.V2.C
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AutopilotMonitor.SummaryDialog.Tests", "src\Agent\AutopilotMonitor.SummaryDialog.Tests\AutopilotMonitor.SummaryDialog.Tests.csproj", "{4F1234C1-9387-4D2C-93E0-713698A2DFCB}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Push", "Push", "{09266D87-DDB8-2F61-A22F-10D1DD295F4F}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AutopilotMonitor.Push", "src\Push\AutopilotMonitor.Push\AutopilotMonitor.Push.csproj", "{2C3E71E4-0049-45A5-839D-F4171B47D5F3}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AutopilotMonitor.Push.Tests", "src\Push\AutopilotMonitor.Push.Tests\AutopilotMonitor.Push.Tests.csproj", "{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -161,6 +167,30 @@ Global
 		{4F1234C1-9387-4D2C-93E0-713698A2DFCB}.Release|x64.Build.0 = Release|Any CPU
 		{4F1234C1-9387-4D2C-93E0-713698A2DFCB}.Release|x86.ActiveCfg = Release|Any CPU
 		{4F1234C1-9387-4D2C-93E0-713698A2DFCB}.Release|x86.Build.0 = Release|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Debug|x64.Build.0 = Debug|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Debug|x86.Build.0 = Debug|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Release|x64.ActiveCfg = Release|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Release|x64.Build.0 = Release|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Release|x86.ActiveCfg = Release|Any CPU
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3}.Release|x86.Build.0 = Release|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Debug|x64.Build.0 = Debug|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Debug|x86.Build.0 = Debug|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Release|Any CPU.Build.0 = Release|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Release|x64.ActiveCfg = Release|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Release|x64.Build.0 = Release|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Release|x86.ActiveCfg = Release|Any CPU
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -179,5 +209,8 @@ Global
 		{11B36E5C-B512-4D1E-A76B-E5AD866B033C} = {096B6098-F141-7114-B090-72D1899D8853}
 		{95A09BF0-4E22-41D9-9B43-8D6ECC2C8AD0} = {096B6098-F141-7114-B090-72D1899D8853}
 		{4F1234C1-9387-4D2C-93E0-713698A2DFCB} = {096B6098-F141-7114-B090-72D1899D8853}
+		{09266D87-DDB8-2F61-A22F-10D1DD295F4F} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
+		{2C3E71E4-0049-45A5-839D-F4171B47D5F3} = {09266D87-DDB8-2F61-A22F-10D1DD295F4F}
+		{6BB95C52-F9D5-4C48-A107-B2B1FD5EE302} = {09266D87-DDB8-2F61-A22F-10D1DD295F4F}
 	EndGlobalSection
 EndGlobal

rules/analyze/ANALYZE-DEV-004.json

@@ -2,10 +2,10 @@
   "$schema": "../schema/analyze-rule.schema.json",
   "ruleId": "ANALYZE-DEV-004",
   "title": "Windows Update Failed During Enrollment",
-  "description": "Detects a Windows quality/cumulative update that FAILED to install during the OOBE / ESP enrollment window (WindowsUpdateClient EventID 20). A cumulative update failing mid-OOBE is a known cause of enrollment errors and is otherwise invisible in the Intune console.",
+  "description": "Detects a Windows quality/cumulative update that FAILED to install or download during the OOBE / ESP enrollment window (WindowsUpdateClient EventID 20 from the System log, 31 from the Operational channel). A cumulative update failing mid-OOBE is a known cause of enrollment errors and is otherwise invisible in the Intune console.",
   "severity": "high",
   "category": "device",
-  "version": "1.1.0",
+  "version": "1.2.0",
   "enabled": true,
   "evaluateOn": [
     "enrollment_end",
@@ -18,10 +18,14 @@
   "conditions": [
     {
       "signal": "wu_install_failed",
-      "source": "event_type",
+      "source": "event_data",
       "eventType": "windows_update_failed",
+      "dataField": "wuEventId",
       "operator": "exists",
       "value": "",
+      "filterField": "wuPhase",
+      "filterOperator": "in",
+      "filterValue": "install,download",
       "required": true
     },
     {
@@ -31,6 +35,9 @@
       "dataField": "updateTitle",
       "operator": "exists",
       "value": "",
+      "filterField": "wuPhase",
+      "filterOperator": "in",
+      "filterValue": "install,download",
       "required": false
     },
     {
@@ -40,6 +47,9 @@
       "dataField": "hresult",
       "operator": "exists",
       "value": "",
+      "filterField": "wuPhase",
+      "filterOperator": "in",
+      "filterValue": "install,download",
       "required": false
     },
     {
@@ -49,6 +59,9 @@
       "dataField": "hresultSymbol",
       "operator": "exists",
       "value": "",
+      "filterField": "wuPhase",
+      "filterOperator": "in",
+      "filterValue": "install,download",
       "required": false
     },
     {

rules/analyze/ANALYZE-DEV-007.json

@@ -5,7 +5,7 @@
   "description": "The device's real-time clock deviates from NTP by more than two minutes. Microsoft documents that a clock off by several minutes causes TPM attestation errors (self-deploying/pre-provisioning) and ESP timeouts.",
   "severity": "warning",
   "category": "device",
-  "version": "1.1.0",
+  "version": "1.1.1",
   "author": "Autopilot Monitor",
   "enabled": true,
   "evaluateOn": [
@@ -17,7 +17,7 @@
   "confidenceThreshold": 50,
   "conditions": [
     {
-      "signal": "clock_ahead",
+      "signal": "clock_behind",
       "source": "event_data",
       "eventType": "ntp_time_check",
       "dataField": "offsetSeconds",
@@ -26,7 +26,7 @@
       "required": false
     },
     {
-      "signal": "clock_behind",
+      "signal": "clock_ahead",
       "source": "event_data",
       "eventType": "ntp_time_check",
       "dataField": "offsetSeconds",

rules/analyze/ANALYZE-DEV-013.json

@@ -0,0 +1,118 @@
+{
+  "$schema": "../schema/analyze-rule.schema.json",
+  "ruleId": "ANALYZE-DEV-013",
+  "title": "OOBE Quality Update Failed",
+  "description": "Detects that the Windows quality update page at the end of OOBE (Enrollment Status Page setting \"Install Windows quality updates\") reported a failed download or install and recorded no successful install afterwards — the page's own failure names on the oobe_update_page events. Setup usually continues, so the failure is otherwise invisible: the device finishes OOBE without the monthly security update. An OS build change across a restart (os_build_changed) vetoes the finding, and so does the agent's names_capped marker — once the page's event names were capped, a missing success name proves nothing. A downloadInstallFailureHelper entry alone is no failure: updates that installed fine log it too.",
+  "severity": "warning",
+  "category": "device",
+  "version": "1.0.0",
+  "enabled": true,
+  "evaluateOn": [
+    "enrollment_end"
+  ],
+  "trigger": "single",
+  "baseConfidence": 75,
+  "confidenceThreshold": 60,
+  "conditions": [
+    {
+      "signal": "update_failure",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "in",
+      "value": "SdxWebAppCloudNDUP_processStatusChangeFromHandler_downloadFailedError,SdxWebAppCloudNDUP_processStatusChangeFromHandler_installFailedError,ExpeditedUpdate_commitExpeditionDownloadInstallAsyncFailure",
+      "required": true
+    },
+    {
+      "signal": "no_install_success",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "name",
+      "filterOperator": "regex",
+      "filterValue": "installSucceededRebootRequired|commitExpeditionDownloadInstallAsyncSucceeded",
+      "required": true
+    },
+    {
+      "signal": "os_build_unchanged",
+      "source": "event_type",
+      "eventType": "os_build_changed",
+      "operator": "not_exists",
+      "value": "",
+      "required": true
+    },
+    {
+      "signal": "page_names_complete",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "cxhEvent",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "cxhEvent",
+      "filterOperator": "equals",
+      "filterValue": "names_capped",
+      "required": true
+    },
+    {
+      "signal": "update_page_failed",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "result",
+      "operator": "equals",
+      "value": "fail",
+      "filterField": "page",
+      "filterOperator": "equals",
+      "filterValue": "OobeNDUP",
+      "required": false
+    },
+    {
+      "signal": "update_skipped",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "regex",
+      "value": "SkipDownloadInstallButtonClicked$",
+      "required": false
+    }
+  ],
+  "confidenceFactors": [
+    {
+      "signal": "update_page_failed",
+      "condition": "exists",
+      "weight": 10
+    }
+  ],
+  "explanation": "The Windows quality update page at the end of OOBE reported `{{update_failure}}`, and no successful install was recorded afterwards. When the download or install of the update fails, the page gives up and setup continues, so the enrollment itself can still succeed — but the device most likely finished OOBE without the monthly security update and installs it only later, through the Windows Update policy that applies after enrollment. Selecting Skip on the page after the failure leads to the same result.",
+  "remediation": [
+    {
+      "title": "Find out why the update failed",
+      "steps": [
+        "Open the oobe_update_page events around the failure in the session timeline: the download progress before it shows how far the download got, and a Skip after it shows that someone chose to continue.",
+        "Check the network path the device uses during OOBE for Windows Update and Delivery Optimization: proxy, TLS inspection and firewall rules for the Windows Update endpoints.",
+        "Compare with other devices: the same failure on many devices of one site points at the network path, on one model at the device, and across the fleet at the update itself."
+      ]
+    },
+    {
+      "title": "Make sure the device gets the update",
+      "steps": [
+        "Verify the device's patch level after enrollment; the update ring assigned to the device installs the missing monthly security update on its normal schedule.",
+        "Where the OOBE quality update keeps failing for one network or device group, decide per Enrollment Status Page profile whether \"Install Windows quality updates\" should stay on."
+      ]
+    }
+  ],
+  "relatedDocs": [
+    {
+      "title": "Microsoft Learn: Install Windows quality updates during OOBE (Enrollment Status Page)",
+      "url": "https://learn.microsoft.com/en-us/intune/device-enrollment/windows/setup-status-page#windows-monthly-security-update-release-details"
+    }
+  ],
+  "markSessionAsFailedDefault": false,
+  "tags": [
+    "device",
+    "windows-update",
+    "oobe",
+    "quality-update"
+  ]
+}

rules/analyze/ANALYZE-DEV-014.json

@@ -0,0 +1,119 @@
+{
+  "$schema": "../schema/analyze-rule.schema.json",
+  "ruleId": "ANALYZE-DEV-014",
+  "title": "OOBE Quality Update Not Offered After an Earlier Failure",
+  "description": "Detects that the Windows quality update page at the end of OOBE found no update to install although the device is out of date, on a device whose update page counts an earlier failed download or install (oobe_update_page: NDUPDownloadInstallPreviousFailureCount above 0, osUpdatesWithNDUPPI false, getDaysOutOfDateSucceeded above 0). No failure and no install success are recorded in this session — a failure in this session is ANALYZE-DEV-013 — and the agent's names_capped marker vetoes the finding, because a missing name proves nothing once the page's names were capped. The device finishes OOBE without the monthly security update.",
+  "severity": "warning",
+  "category": "device",
+  "version": "1.0.0",
+  "enabled": true,
+  "evaluateOn": [
+    "enrollment_end"
+  ],
+  "trigger": "single",
+  "baseConfidence": 75,
+  "confidenceThreshold": 60,
+  "conditions": [
+    {
+      "signal": "previous_failures",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "value",
+      "operator": "gt",
+      "value": "0",
+      "filterField": "name",
+      "filterOperator": "equals",
+      "filterValue": "SdxWebAppCloudNDUP_initialize_NDUPDownloadInstallPreviousFailureCount",
+      "required": true
+    },
+    {
+      "signal": "nothing_offered",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "value",
+      "operator": "equals",
+      "value": "false",
+      "filterField": "name",
+      "filterOperator": "equals",
+      "filterValue": "SdxWebAppCloudNDUP_updateManager_processUpdatesMetadata_osUpdatesWithNDUPPI",
+      "required": true
+    },
+    {
+      "signal": "days_out_of_date",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "value",
+      "operator": "gt",
+      "value": "0",
+      "filterField": "name",
+      "filterOperator": "equals",
+      "filterValue": "ExpeditedUpdate_getDaysOutOfDateSucceeded",
+      "required": true
+    },
+    {
+      "signal": "no_update_failure",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "name",
+      "filterOperator": "in",
+      "filterValue": "SdxWebAppCloudNDUP_processStatusChangeFromHandler_downloadFailedError,SdxWebAppCloudNDUP_processStatusChangeFromHandler_installFailedError,ExpeditedUpdate_commitExpeditionDownloadInstallAsyncFailure",
+      "required": true
+    },
+    {
+      "signal": "no_install_success",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "name",
+      "filterOperator": "regex",
+      "filterValue": "installSucceededRebootRequired|commitExpeditionDownloadInstallAsyncSucceeded",
+      "required": true
+    },
+    {
+      "signal": "page_names_complete",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "cxhEvent",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "cxhEvent",
+      "filterOperator": "equals",
+      "filterValue": "names_capped",
+      "required": true
+    }
+  ],
+  "explanation": "The Windows quality update page at the end of OOBE checked for updates and found none to install, although Windows reports the device as {{days_out_of_date}} days out of date. The page's failure counter for this device stands at {{previous_failures}}: an earlier download or install of an OOBE quality update on this device failed. The device finished OOBE without the monthly security update and installs it only later, through the Windows Update policy that applies after enrollment.",
+  "remediation": [
+    {
+      "title": "Check the earlier attempt",
+      "steps": [
+        "Look at the device's earlier enrollment sessions — the failed attempt and its ANALYZE-DEV-013 finding are usually there.",
+        "Verify the device's patch level after enrollment; the update ring assigned to the device installs the missing monthly security update on its normal schedule."
+      ]
+    },
+    {
+      "title": "Reduce how far behind devices start",
+      "steps": [
+        "Devices that start OOBE many months behind need a long update during setup; a current OS image or factory build shortens it and gives a failed attempt less to repeat."
+      ]
+    }
+  ],
+  "relatedDocs": [
+    {
+      "title": "Microsoft Learn: Install Windows quality updates during OOBE (Enrollment Status Page)",
+      "url": "https://learn.microsoft.com/en-us/intune/device-enrollment/windows/setup-status-page#windows-monthly-security-update-release-details"
+    }
+  ],
+  "markSessionAsFailedDefault": false,
+  "tags": [
+    "device",
+    "windows-update",
+    "oobe",
+    "quality-update"
+  ]
+}

rules/analyze/ANALYZE-DEV-015.json

@@ -0,0 +1,117 @@
+{
+  "$schema": "../schema/analyze-rule.schema.json",
+  "ruleId": "ANALYZE-DEV-015",
+  "title": "OOBE Update Check Ended Without a Result",
+  "description": "Detects that the Windows quality update page at the end of OOBE started its Windows Update scan but ended without a scan result (oobe_update_page: startWUScanStartedSuccedded, an OobeNDUP stop and no ExpeditedUpdate_getUpdateResults name), on a device that is out of date and allowed to update. In the observed sessions the page ended two minutes after the scan started, on devices more than a year behind. The device finishes OOBE without the monthly security update. The agent's names_capped marker vetoes the finding: once the page's event names were capped, a missing scan result proves nothing.",
+  "severity": "warning",
+  "category": "device",
+  "version": "1.0.0",
+  "enabled": true,
+  "evaluateOn": [
+    "enrollment_end"
+  ],
+  "trigger": "single",
+  "baseConfidence": 75,
+  "confidenceThreshold": 60,
+  "conditions": [
+    {
+      "signal": "update_allowed",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "value",
+      "operator": "equals",
+      "value": "true",
+      "filterField": "name",
+      "filterOperator": "equals",
+      "filterValue": "ExpeditedUpdate_isNDUPAllowedByCSPSucceeded",
+      "required": true
+    },
+    {
+      "signal": "scan_started",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "equals",
+      "value": "ExpeditedUpdate_startWUScanStartedSuccedded",
+      "required": true
+    },
+    {
+      "signal": "no_scan_result",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "name",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "name",
+      "filterOperator": "regex",
+      "filterValue": "^ExpeditedUpdate_getUpdateResults",
+      "required": true
+    },
+    {
+      "signal": "update_page_ended",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "cxhEvent",
+      "operator": "equals",
+      "value": "page_stopped",
+      "filterField": "page",
+      "filterOperator": "equals",
+      "filterValue": "OobeNDUP",
+      "required": true
+    },
+    {
+      "signal": "days_out_of_date",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "value",
+      "operator": "gt",
+      "value": "0",
+      "filterField": "name",
+      "filterOperator": "equals",
+      "filterValue": "ExpeditedUpdate_getDaysOutOfDateSucceeded",
+      "required": true
+    },
+    {
+      "signal": "page_names_complete",
+      "source": "event_data",
+      "eventType": "oobe_update_page",
+      "dataField": "cxhEvent",
+      "operator": "not_exists",
+      "value": "",
+      "filterField": "cxhEvent",
+      "filterOperator": "equals",
+      "filterValue": "names_capped",
+      "required": true
+    }
+  ],
+  "explanation": "The Windows quality update page at the end of OOBE started a Windows Update scan, but no scan result arrived before the page ended. The device is {{days_out_of_date}} days out of date, so an update was due — the device finished OOBE without the monthly security update and installs it only later, through the Windows Update policy that applies after enrollment. The page waits only a short time for the scan (two minutes in the observed sessions): a scan that takes longer, or cannot reach Windows Update, ends the page without an update.",
+  "remediation": [
+    {
+      "title": "Check the path to Windows Update during OOBE",
+      "steps": [
+        "Verify that devices in OOBE reach the Windows Update service: proxy, TLS inspection and firewall rules for the Windows Update endpoints.",
+        "Check whether an update policy applied during the Enrollment Status Page points the scan at another source, such as WSUS."
+      ]
+    },
+    {
+      "title": "Shorten the scan",
+      "steps": [
+        "Devices far behind scan longer; a current OS image or factory build keeps the OOBE scan short.",
+        "Verify the device's patch level after enrollment; the update ring assigned to the device installs the missing monthly security update on its normal schedule."
+      ]
+    }
+  ],
+  "relatedDocs": [
+    {
+      "title": "Microsoft Learn: Install Windows quality updates during OOBE (Enrollment Status Page)",
+      "url": "https://learn.microsoft.com/en-us/intune/device-enrollment/windows/setup-status-page#windows-monthly-security-update-release-details"
+    }
+  ],
+  "markSessionAsFailedDefault": false,
+  "tags": [
+    "device",
+    "windows-update",
+    "oobe",
+    "quality-update"
+  ]
+}

rules/analyze/ANALYZE-ESP-004.json

@@ -1,11 +1,11 @@
 {
   "$schema": "../schema/analyze-rule.schema.json",
   "ruleId": "ANALYZE-ESP-004",
-  "title": "ESP Timeout with 'Continue Anyway' (Soft Failure)",
-  "description": "Detects an ESP terminal failure on a profile that allows 'Continue anyway'. The enrollment is reported as failed, but the user most likely dismissed the error screen and reached the desktop — a soft failure rather than an unusable device.",
+  "title": "ESP Gave Up on a Blocking App with 'Continue Anyway' (Soft Failure)",
+  "description": "Detects an ESP terminal failure where the ESP gave up while a blocking app was still installing (the agent's own esp_apps_timeout verdict — no per-app HRESULT was reported) on a profile that allows 'Continue anyway'. The enrollment is reported as failed, but the user most likely dismissed the error screen and reached the desktop — a soft failure rather than an unusable device. An ESP failure that carries a specific error code (a failed installer, a detection mismatch) is a different case and stays with the rule that explains that code.",
   "severity": "warning",
   "category": "esp",
-  "version": "1.0.1",
+  "version": "1.1.0",
   "enabled": true,
   "baseConfidence": 80,
   "conditions": [
@@ -26,6 +26,27 @@
       "value": "true",
       "required": true
     },
+    {
+      "signal": "esp_gave_up_on_app",
+      "source": "event_type",
+      "eventType": "app_install_failed",
+      "dataField": "failureType",
+      "operator": "equals",
+      "value": "esp_apps_timeout",
+      "required": true
+    },
+    {
+      "signal": "appName",
+      "source": "event_data",
+      "eventType": "app_install_failed",
+      "dataField": "appName",
+      "operator": "exists",
+      "value": "",
+      "filterField": "failureType",
+      "filterOperator": "equals",
+      "filterValue": "esp_apps_timeout",
+      "required": false
+    },
     {
       "signal": "espSyncFailureTimeoutMinutes",
       "source": "event_type",
@@ -38,34 +59,25 @@
     {
       "signal": "failedSubcategory",
       "source": "event_type",
-      "eventType": "enrollment_failed",
+      "eventType": "esp_failure_settle_started",
       "dataField": "failedSubcategory",
       "operator": "exists",
       "value": "",
       "required": false
-    },
-    {
-      "signal": "appName",
-      "source": "event_type",
-      "eventType": "app_install_failed",
-      "dataField": "appName",
-      "operator": "exists",
-      "value": "",
-      "required": false
     }
   ],
   "confidenceFactors": [
-    { "signal": "appName", "condition": "exists", "weight": 10 }
+    { "signal": "failedSubcategory", "condition": "exists", "weight": 10 }
   ],
-  "explanation": "This enrollment was reported as **failed** because the Enrollment Status Page reached its configured terminal timeout (`{{espSyncFailureTimeoutMinutes}} min`) before all blocking items finished. The ESP profile, however, allows **'Continue anyway'** — so the user most likely dismissed the error screen and reached the desktop with a working, though not fully provisioned, device.\n\nThe agent only observes the ESP terminal failure on the device side; it cannot see what the user did after the failure screen. Treat this as a **soft failure**: the device may well be in productive use, while at least one blocking item (`{{failedSubcategory}}` subcategory / app `{{appName}}`) did not complete inside the ESP window.\n\nA cluster of these across a tenant almost always points at one slow blocking app holding the whole fleet at the ESP timeout wall, not at broken devices. Any field still shown as a literal `{{…}}` placeholder was simply not recorded for this session (e.g. a certificate-only failure has no failed app).",
+  "explanation": "This enrollment was reported as **failed** because the Enrollment Status Page gave up while the blocking app **{{appName}}** was still installing — the agent recorded no per-app error code, only that the app never finished inside the ESP window (the profile's configured limit is `{{espSyncFailureTimeoutMinutes}} min`; the ESP may have stopped earlier than that). The ESP profile, however, allows **'Continue anyway'** — so the user most likely dismissed the error screen and reached the desktop with a working, though not fully provisioned, device.\n\nThe agent only observes the ESP terminal failure on the device side; it cannot see what the user did after the failure screen. Treat this as a **soft failure**: the device may well be in productive use, while the `{{failedSubcategory}}` subcategory did not complete inside the ESP window.\n\nA cluster of these across a tenant almost always points at one slow blocking app holding the whole fleet at the ESP limit, not at broken devices. This rule deliberately stays silent when the failed app reported a specific error code — a failed installer or a detection mismatch is explained by the rule for that code, and 'Continue anyway' does not make it a timing problem. Any field still shown as a literal `{{…}}` placeholder was simply not recorded for this session.",
   "remediation": [
     {
       "title": "Relieve ESP pressure so enrollments finish inside the window",
       "steps": [
-        "Identify the slow blocking app (`{{appName}}`) and either remove it from the ESP 'block device use until these required apps are installed' list, or raise the ESP installation timeout (currently {{espSyncFailureTimeoutMinutes}} min).",
-        "If the app legitimately needs longer than the ESP allows, make it non-blocking and let it install after the desktop arrives.",
-        "Verify the app's detection rule matches after install — an app that installs but fails detection times out the ESP on every device (see ANALYZE-APP-013).",
-        "If a subcategory such as Certificates is reported under '{{failedSubcategory}}', confirm the certificate/connector actually delivers — 'Continue anyway' hides a missing certificate, it does not fix it."
+        "Look at how long `{{appName}}` takes on a device that completes: if it legitimately needs longer than the ESP allows, make it non-blocking (remove it from 'block device use until these required apps are installed') and let it install after the desktop arrives.",
+        "If the app must stay blocking, raise the ESP setting 'Show error when installation takes longer than' (configured at {{espSyncFailureTimeoutMinutes}} min) — a limit, not a target; it only helps when the app reliably finishes within the new value.",
+        "Check the app's dependencies and install order: a blocking app waiting on a large dependency download (Delivery Optimization, proxy throughput) is the usual reason it never finishes in time.",
+        "If the ESP reported a non-Apps subcategory under '{{failedSubcategory}}', confirm the certificate/connector actually delivers — 'Continue anyway' hides a missing certificate, it does not fix it."
       ]
     }
   ],

rules/analyze/ANALYZE-ID-001.json

@@ -5,6 +5,7 @@
   "description": "Detects when a certificate with the configured subject is missing from the local machine personal store (LocalMachine\\My). Requires the gather rule GATHER-ID-002 (machine cert store inventory) to be enabled — the check runs against its gather_machine_cert_store output. A missing certificate may indicate that MDM enrollment certificate provisioning or SCEP certificate deployment failed.",
   "severity": "warning",
   "category": "identity",
+  "author": "Community",
   "isCommunity": true,
   "enabled": false,
   "evaluateOn": [

rules/analyze/ANALYZE-OFFICE-001.json

@@ -2,10 +2,10 @@
   "$schema": "../schema/analyze-rule.schema.json",
   "ruleId": "ANALYZE-OFFICE-001",
   "title": "Microsoft 365 Apps Install Failed",
-  "description": "Detects when the Microsoft 365 Apps (Office Click-to-Run) background install did not reach completion. The V2 OfficeInstallDetector watches the C2R client directly (registry + process) and emits office_install_failed when the install scenario was abandoned (worker gone and streaming never finished) or a C2R failure code was observed. This catches Office failures that the Intune integrated app type hides, because IME reports the app done within 1-2 minutes while C2R keeps installing in the background.",
+  "description": "Detects when the Microsoft 365 Apps (Office Click-to-Run) install failed. The V2 OfficeInstallDetector watches the C2R client directly (registry, Delivery Optimization, process) and emits office_install_failed when the C2R INSTALL scenario records an error code. Completion is proven by the core Office binaries on disk; an install window that closes without that proof ends silently, never as a failure. This catches Office failures the deployment status hides: the Intune built-in app type is marked done once the configuration is delivered, and a Win32 or RealmJoin package once its installer exits, while C2R keeps installing in the background.",
   "severity": "warning",
   "category": "apps",
-  "version": "1.1.0",
+  "version": "1.1.1",
   "enabled": true,
   "evaluateOn": [
     "enrollment_end",
@@ -39,12 +39,12 @@
     }
   ],
   "confidenceThreshold": 40,
-  "explanation": "The Microsoft 365 Apps (Office Click-to-Run) install did not finish.\n\nThe OfficeInstallDetector watches the C2R client directly and reports the real background install lifecycle. The Intune \"integrated\" Microsoft 365 Apps app type only pushes the configuration XML and starts the C2R bootstrapper, so IME marks the app done within 1-2 minutes while C2R keeps streaming and laying down the product for several more minutes. This event means C2R activity ended (the OfficeC2RClient worker exited and the install scenario cleared) without the StreamingFinished flag being set, or a C2R failure code was observed.\n\nReview the office_install_failed event payload: `products`, `channel`, `phase`, `streamingFinished`, `errorCode` (best-effort — may be empty) and `durationSeconds`.",
+  "explanation": "The Microsoft 365 Apps (Office Click-to-Run) install failed.\n\nThe OfficeInstallDetector watches the C2R client directly and reports the real install lifecycle, however it was started. The Intune built-in Microsoft 365 Apps app type delivers the configuration through the Office CSP and lets the device start C2R; a Win32 or RealmJoin package runs the Office Deployment Tool. Either way the deployment is marked done before C2R has finished laying down the product. This event means C2R recorded an error code in its INSTALL scenario before the core Office apps were on disk.\n\nReview the office_install_failed event payload: `products`, `channel`, `errorCode`, `errorSource` (the C2R registry value that carried the code) and `durationSeconds`.",
   "remediation": [
     {
       "title": "Investigate the Office C2R install failure",
       "steps": [
-        "Open the office_install_failed event and review products, channel, phase, streamingFinished and errorCode",
+        "Open the office_install_failed event and review products, channel, errorCode and errorSource",
         "Check the Click-to-Run logs on the device (%windir%\\Temp and %temp%, files named <MachineName>-yyyymmdd-nnnn.log) for the failing operation",
         "Verify the device had network reachability to the Office CDN / Microsoft Connected Cache during the enrollment window",
         "Confirm the Intune Microsoft 365 Apps app configuration (products, channel, architecture) matches what the device can install",

rules/dist/analyze-rules.json

@@ -1385,10 +1385,10 @@
     {
       "ruleId": "ANALYZE-DEV-004",
       "title": "Windows Update Failed During Enrollment",
-      "description": "Detects a Windows quality/cumulative update that FAILED to install during the OOBE / ESP enrollment window (WindowsUpdateClient EventID 20). A cumulative update failing mid-OOBE is a known cause of enrollment errors and is otherwise invisible in the Intune console.",
+      "description": "Detects a Windows quality/cumulative update that FAILED to install or download during the OOBE / ESP enrollment window (WindowsUpdateClient EventID 20 from the System log, 31 from the Operational channel). A cumulative update failing mid-OOBE is a known cause of enrollment errors and is otherwise invisible in the Intune console.",
       "severity": "high",
       "category": "device",
-      "version": "1.1.0",
+      "version": "1.2.0",
       "enabled": true,
       "evaluateOn": [
         "enrollment_end",
@@ -1401,10 +1401,14 @@
       "conditions": [
         {
           "signal": "wu_install_failed",
-          "source": "event_type",
+          "source": "event_data",
           "eventType": "windows_update_failed",
+          "dataField": "wuEventId",
           "operator": "exists",
           "value": "",
+          "filterField": "wuPhase",
+          "filterOperator": "in",
+          "filterValue": "install,download",
           "required": true
         },
         {
@@ -1414,6 +1418,9 @@
           "dataField": "updateTitle",
           "operator": "exists",
           "value": "",
+          "filterField": "wuPhase",
+          "filterOperator": "in",
+          "filterValue": "install,download",
           "required": false
         },
         {
@@ -1423,6 +1430,9 @@
           "dataField": "hresult",
           "operator": "exists",
           "value": "",
+          "filterField": "wuPhase",
+          "filterOperator": "in",
+          "filterValue": "install,download",
           "required": false
         },
         {
@@ -1432,6 +1442,9 @@
           "dataField": "hresultSymbol",
           "operator": "exists",
           "value": "",
+          "filterField": "wuPhase",
+          "filterOperator": "in",
+          "filterValue": "install,download",
           "required": false
         },
         {
@@ -1641,7 +1654,7 @@
       "description": "The device's real-time clock deviates from NTP by more than two minutes. Microsoft documents that a clock off by several minutes causes TPM attestation errors (self-deploying/pre-provisioning) and ESP timeouts.",
       "severity": "warning",
       "category": "device",
-      "version": "1.1.0",
+      "version": "1.1.1",
       "author": "Autopilot Monitor",
       "enabled": true,
       "evaluateOn": [
@@ -1653,7 +1666,7 @@
       "confidenceThreshold": 50,
       "conditions": [
         {
-          "signal": "clock_ahead",
+          "signal": "clock_behind",
           "source": "event_data",
           "eventType": "ntp_time_check",
           "dataField": "offsetSeconds",
@@ -1662,7 +1675,7 @@
           "required": false
         },
         {
-          "signal": "clock_behind",
+          "signal": "clock_ahead",
           "source": "event_data",
           "eventType": "ntp_time_check",
           "dataField": "offsetSeconds",
@@ -1917,6 +1930,357 @@
         "environment"
       ]
     },
+    {
+      "ruleId": "ANALYZE-DEV-013",
+      "title": "OOBE Quality Update Failed",
+      "description": "Detects that the Windows quality update page at the end of OOBE (Enrollment Status Page setting \"Install Windows quality updates\") reported a failed download or install and recorded no successful install afterwards — the page's own failure names on the oobe_update_page events. Setup usually continues, so the failure is otherwise invisible: the device finishes OOBE without the monthly security update. An OS build change across a restart (os_build_changed) vetoes the finding, and so does the agent's names_capped marker — once the page's event names were capped, a missing success name proves nothing. A downloadInstallFailureHelper entry alone is no failure: updates that installed fine log it too.",
+      "severity": "warning",
+      "category": "device",
+      "version": "1.0.0",
+      "enabled": true,
+      "evaluateOn": [
+        "enrollment_end"
+      ],
+      "trigger": "single",
+      "baseConfidence": 75,
+      "confidenceThreshold": 60,
+      "conditions": [
+        {
+          "signal": "update_failure",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "in",
+          "value": "SdxWebAppCloudNDUP_processStatusChangeFromHandler_downloadFailedError,SdxWebAppCloudNDUP_processStatusChangeFromHandler_installFailedError,ExpeditedUpdate_commitExpeditionDownloadInstallAsyncFailure",
+          "required": true
+        },
+        {
+          "signal": "no_install_success",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "name",
+          "filterOperator": "regex",
+          "filterValue": "installSucceededRebootRequired|commitExpeditionDownloadInstallAsyncSucceeded",
+          "required": true
+        },
+        {
+          "signal": "os_build_unchanged",
+          "source": "event_type",
+          "eventType": "os_build_changed",
+          "operator": "not_exists",
+          "value": "",
+          "required": true
+        },
+        {
+          "signal": "page_names_complete",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "cxhEvent",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "cxhEvent",
+          "filterOperator": "equals",
+          "filterValue": "names_capped",
+          "required": true
+        },
+        {
+          "signal": "update_page_failed",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "result",
+          "operator": "equals",
+          "value": "fail",
+          "filterField": "page",
+          "filterOperator": "equals",
+          "filterValue": "OobeNDUP",
+          "required": false
+        },
+        {
+          "signal": "update_skipped",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "regex",
+          "value": "SkipDownloadInstallButtonClicked$",
+          "required": false
+        }
+      ],
+      "confidenceFactors": [
+        {
+          "signal": "update_page_failed",
+          "condition": "exists",
+          "weight": 10
+        }
+      ],
+      "explanation": "The Windows quality update page at the end of OOBE reported `{{update_failure}}`, and no successful install was recorded afterwards. When the download or install of the update fails, the page gives up and setup continues, so the enrollment itself can still succeed — but the device most likely finished OOBE without the monthly security update and installs it only later, through the Windows Update policy that applies after enrollment. Selecting Skip on the page after the failure leads to the same result.",
+      "remediation": [
+        {
+          "title": "Find out why the update failed",
+          "steps": [
+            "Open the oobe_update_page events around the failure in the session timeline: the download progress before it shows how far the download got, and a Skip after it shows that someone chose to continue.",
+            "Check the network path the device uses during OOBE for Windows Update and Delivery Optimization: proxy, TLS inspection and firewall rules for the Windows Update endpoints.",
+            "Compare with other devices: the same failure on many devices of one site points at the network path, on one model at the device, and across the fleet at the update itself."
+          ]
+        },
+        {
+          "title": "Make sure the device gets the update",
+          "steps": [
+            "Verify the device's patch level after enrollment; the update ring assigned to the device installs the missing monthly security update on its normal schedule.",
+            "Where the OOBE quality update keeps failing for one network or device group, decide per Enrollment Status Page profile whether \"Install Windows quality updates\" should stay on."
+          ]
+        }
+      ],
+      "relatedDocs": [
+        {
+          "title": "Microsoft Learn: Install Windows quality updates during OOBE (Enrollment Status Page)",
+          "url": "https://learn.microsoft.com/en-us/intune/device-enrollment/windows/setup-status-page#windows-monthly-security-update-release-details"
+        }
+      ],
+      "markSessionAsFailedDefault": false,
+      "tags": [
+        "device",
+        "windows-update",
+        "oobe",
+        "quality-update"
+      ]
+    },
+    {
+      "ruleId": "ANALYZE-DEV-014",
+      "title": "OOBE Quality Update Not Offered After an Earlier Failure",
+      "description": "Detects that the Windows quality update page at the end of OOBE found no update to install although the device is out of date, on a device whose update page counts an earlier failed download or install (oobe_update_page: NDUPDownloadInstallPreviousFailureCount above 0, osUpdatesWithNDUPPI false, getDaysOutOfDateSucceeded above 0). No failure and no install success are recorded in this session — a failure in this session is ANALYZE-DEV-013 — and the agent's names_capped marker vetoes the finding, because a missing name proves nothing once the page's names were capped. The device finishes OOBE without the monthly security update.",
+      "severity": "warning",
+      "category": "device",
+      "version": "1.0.0",
+      "enabled": true,
+      "evaluateOn": [
+        "enrollment_end"
+      ],
+      "trigger": "single",
+      "baseConfidence": 75,
+      "confidenceThreshold": 60,
+      "conditions": [
+        {
+          "signal": "previous_failures",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "value",
+          "operator": "gt",
+          "value": "0",
+          "filterField": "name",
+          "filterOperator": "equals",
+          "filterValue": "SdxWebAppCloudNDUP_initialize_NDUPDownloadInstallPreviousFailureCount",
+          "required": true
+        },
+        {
+          "signal": "nothing_offered",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "value",
+          "operator": "equals",
+          "value": "false",
+          "filterField": "name",
+          "filterOperator": "equals",
+          "filterValue": "SdxWebAppCloudNDUP_updateManager_processUpdatesMetadata_osUpdatesWithNDUPPI",
+          "required": true
+        },
+        {
+          "signal": "days_out_of_date",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "value",
+          "operator": "gt",
+          "value": "0",
+          "filterField": "name",
+          "filterOperator": "equals",
+          "filterValue": "ExpeditedUpdate_getDaysOutOfDateSucceeded",
+          "required": true
+        },
+        {
+          "signal": "no_update_failure",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "name",
+          "filterOperator": "in",
+          "filterValue": "SdxWebAppCloudNDUP_processStatusChangeFromHandler_downloadFailedError,SdxWebAppCloudNDUP_processStatusChangeFromHandler_installFailedError,ExpeditedUpdate_commitExpeditionDownloadInstallAsyncFailure",
+          "required": true
+        },
+        {
+          "signal": "no_install_success",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "name",
+          "filterOperator": "regex",
+          "filterValue": "installSucceededRebootRequired|commitExpeditionDownloadInstallAsyncSucceeded",
+          "required": true
+        },
+        {
+          "signal": "page_names_complete",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "cxhEvent",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "cxhEvent",
+          "filterOperator": "equals",
+          "filterValue": "names_capped",
+          "required": true
+        }
+      ],
+      "explanation": "The Windows quality update page at the end of OOBE checked for updates and found none to install, although Windows reports the device as {{days_out_of_date}} days out of date. The page's failure counter for this device stands at {{previous_failures}}: an earlier download or install of an OOBE quality update on this device failed. The device finished OOBE without the monthly security update and installs it only later, through the Windows Update policy that applies after enrollment.",
+      "remediation": [
+        {
+          "title": "Check the earlier attempt",
+          "steps": [
+            "Look at the device's earlier enrollment sessions — the failed attempt and its ANALYZE-DEV-013 finding are usually there.",
+            "Verify the device's patch level after enrollment; the update ring assigned to the device installs the missing monthly security update on its normal schedule."
+          ]
+        },
+        {
+          "title": "Reduce how far behind devices start",
+          "steps": [
+            "Devices that start OOBE many months behind need a long update during setup; a current OS image or factory build shortens it and gives a failed attempt less to repeat."
+          ]
+        }
+      ],
+      "relatedDocs": [
+        {
+          "title": "Microsoft Learn: Install Windows quality updates during OOBE (Enrollment Status Page)",
+          "url": "https://learn.microsoft.com/en-us/intune/device-enrollment/windows/setup-status-page#windows-monthly-security-update-release-details"
+        }
+      ],
+      "markSessionAsFailedDefault": false,
+      "tags": [
+        "device",
+        "windows-update",
+        "oobe",
+        "quality-update"
+      ]
+    },
+    {
+      "ruleId": "ANALYZE-DEV-015",
+      "title": "OOBE Update Check Ended Without a Result",
+      "description": "Detects that the Windows quality update page at the end of OOBE started its Windows Update scan but ended without a scan result (oobe_update_page: startWUScanStartedSuccedded, an OobeNDUP stop and no ExpeditedUpdate_getUpdateResults name), on a device that is out of date and allowed to update. In the observed sessions the page ended two minutes after the scan started, on devices more than a year behind. The device finishes OOBE without the monthly security update. The agent's names_capped marker vetoes the finding: once the page's event names were capped, a missing scan result proves nothing.",
+      "severity": "warning",
+      "category": "device",
+      "version": "1.0.0",
+      "enabled": true,
+      "evaluateOn": [
+        "enrollment_end"
+      ],
+      "trigger": "single",
+      "baseConfidence": 75,
+      "confidenceThreshold": 60,
+      "conditions": [
+        {
+          "signal": "update_allowed",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "value",
+          "operator": "equals",
+          "value": "true",
+          "filterField": "name",
+          "filterOperator": "equals",
+          "filterValue": "ExpeditedUpdate_isNDUPAllowedByCSPSucceeded",
+          "required": true
+        },
+        {
+          "signal": "scan_started",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "equals",
+          "value": "ExpeditedUpdate_startWUScanStartedSuccedded",
+          "required": true
+        },
+        {
+          "signal": "no_scan_result",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "name",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "name",
+          "filterOperator": "regex",
+          "filterValue": "^ExpeditedUpdate_getUpdateResults",
+          "required": true
+        },
+        {
+          "signal": "update_page_ended",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "cxhEvent",
+          "operator": "equals",
+          "value": "page_stopped",
+          "filterField": "page",
+          "filterOperator": "equals",
+          "filterValue": "OobeNDUP",
+          "required": true
+        },
+        {
+          "signal": "days_out_of_date",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "value",
+          "operator": "gt",
+          "value": "0",
+          "filterField": "name",
+          "filterOperator": "equals",
+          "filterValue": "ExpeditedUpdate_getDaysOutOfDateSucceeded",
+          "required": true
+        },
+        {
+          "signal": "page_names_complete",
+          "source": "event_data",
+          "eventType": "oobe_update_page",
+          "dataField": "cxhEvent",
+          "operator": "not_exists",
+          "value": "",
+          "filterField": "cxhEvent",
+          "filterOperator": "equals",
+          "filterValue": "names_capped",
+          "required": true
+        }
+      ],
+      "explanation": "The Windows quality update page at the end of OOBE started a Windows Update scan, but no scan result arrived before the page ended. The device is {{days_out_of_date}} days out of date, so an update was due — the device finished OOBE without the monthly security update and installs it only later, through the Windows Update policy that applies after enrollment. The page waits only a short time for the scan (two minutes in the observed sessions): a scan that takes longer, or cannot reach Windows Update, ends the page without an update.",
+      "remediation": [
+        {
+          "title": "Check the path to Windows Update during OOBE",
+          "steps": [
+            "Verify that devices in OOBE reach the Windows Update service: proxy, TLS inspection and firewall rules for the Windows Update endpoints.",
+            "Check whether an update policy applied during the Enrollment Status Page points the scan at another source, such as WSUS."
+          ]
+        },
+        {
+          "title": "Shorten the scan",
+          "steps": [
+            "Devices far behind scan longer; a current OS image or factory build keeps the OOBE scan short.",
+            "Verify the device's patch level after enrollment; the update ring assigned to the device installs the missing monthly security update on its normal schedule."
+          ]
+        }
+      ],
+      "relatedDocs": [
+        {
+          "title": "Microsoft Learn: Install Windows quality updates during OOBE (Enrollment Status Page)",
+          "url": "https://learn.microsoft.com/en-us/intune/device-enrollment/windows/setup-status-page#windows-monthly-security-update-release-details"
+        }
+      ],
+      "markSessionAsFailedDefault": false,
+      "tags": [
+        "device",
+        "windows-update",
+        "oobe",
+        "quality-update"
+      ]
+    },
     {
       "ruleId": "ANALYZE-ENRL-001",
       "title": "Enrollment Failed",
@@ -2496,11 +2860,11 @@
     },
     {
       "ruleId": "ANALYZE-ESP-004",
-      "title": "ESP Timeout with 'Continue Anyway' (Soft Failure)",
-      "description": "Detects an ESP terminal failure on a profile that allows 'Continue anyway'. The enrollment is reported as failed, but the user most likely dismissed the error screen and reached the desktop — a soft failure rather than an unusable device.",
+      "title": "ESP Gave Up on a Blocking App with 'Continue Anyway' (Soft Failure)",
+      "description": "Detects an ESP terminal failure where the ESP gave up while a blocking app was still installing (the agent's own esp_apps_timeout verdict — no per-app HRESULT was reported) on a profile that allows 'Continue anyway'. The enrollment is reported as failed, but the user most likely dismissed the error screen and reached the desktop — a soft failure rather than an unusable device. An ESP failure that carries a specific error code (a failed installer, a detection mismatch) is a different case and stays with the rule that explains that code.",
       "severity": "warning",
       "category": "esp",
-      "version": "1.0.1",
+      "version": "1.1.0",
       "enabled": true,
       "baseConfidence": 80,
       "conditions": [
@@ -2521,6 +2885,27 @@
           "value": "true",
           "required": true
         },
+        {
+          "signal": "esp_gave_up_on_app",
+          "source": "event_type",
+          "eventType": "app_install_failed",
+          "dataField": "failureType",
+          "operator": "equals",
+          "value": "esp_apps_timeout",
+          "required": true
+        },
+        {
+          "signal": "appName",
+          "source": "event_data",
+          "eventType": "app_install_failed",
+          "dataField": "appName",
+          "operator": "exists",
+          "value": "",
+          "filterField": "failureType",
+          "filterOperator": "equals",
+          "filterValue": "esp_apps_timeout",
+          "required": false
+        },
         {
           "signal": "espSyncFailureTimeoutMinutes",
           "source": "event_type",
@@ -2533,38 +2918,29 @@
         {
           "signal": "failedSubcategory",
           "source": "event_type",
-          "eventType": "enrollment_failed",
+          "eventType": "esp_failure_settle_started",
           "dataField": "failedSubcategory",
           "operator": "exists",
           "value": "",
           "required": false
-        },
-        {
-          "signal": "appName",
-          "source": "event_type",
-          "eventType": "app_install_failed",
-          "dataField": "appName",
-          "operator": "exists",
-          "value": "",
-          "required": false
         }
       ],
       "confidenceFactors": [
         {
-          "signal": "appName",
+          "signal": "failedSubcategory",
           "condition": "exists",
           "weight": 10
         }
       ],
-      "explanation": "This enrollment was reported as **failed** because the Enrollment Status Page reached its configured terminal timeout (`{{espSyncFailureTimeoutMinutes}} min`) before all blocking items finished. The ESP profile, however, allows **'Continue anyway'** — so the user most likely dismissed the error screen and reached the desktop with a working, though not fully provisioned, device.\n\nThe agent only observes the ESP terminal failure on the device side; it cannot see what the user did after the failure screen. Treat this as a **soft failure**: the device may well be in productive use, while at least one blocking item (`{{failedSubcategory}}` subcategory / app `{{appName}}`) did not complete inside the ESP window.\n\nA cluster of these across a tenant almost always points at one slow blocking app holding the whole fleet at the ESP timeout wall, not at broken devices. Any field still shown as a literal `{{…}}` placeholder was simply not recorded for this session (e.g. a certificate-only failure has no failed app).",
+      "explanation": "This enrollment was reported as **failed** because the Enrollment Status Page gave up while the blocking app **{{appName}}** was still installing — the agent recorded no per-app error code, only that the app never finished inside the ESP window (the profile's configured limit is `{{espSyncFailureTimeoutMinutes}} min`; the ESP may have stopped earlier than that). The ESP profile, however, allows **'Continue anyway'** — so the user most likely dismissed the error screen and reached the desktop with a working, though not fully provisioned, device.\n\nThe agent only observes the ESP terminal failure on the device side; it cannot see what the user did after the failure screen. Treat this as a **soft failure**: the device may well be in productive use, while the `{{failedSubcategory}}` subcategory did not complete inside the ESP window.\n\nA cluster of these across a tenant almost always points at one slow blocking app holding the whole fleet at the ESP limit, not at broken devices. This rule deliberately stays silent when the failed app reported a specific error code — a failed installer or a detection mismatch is explained by the rule for that code, and 'Continue anyway' does not make it a timing problem. Any field still shown as a literal `{{…}}` placeholder was simply not recorded for this session.",
       "remediation": [
         {
           "title": "Relieve ESP pressure so enrollments finish inside the window",
           "steps": [
-            "Identify the slow blocking app (`{{appName}}`) and either remove it from the ESP 'block device use until these required apps are installed' list, or raise the ESP installation timeout (currently {{espSyncFailureTimeoutMinutes}} min).",
-            "If the app legitimately needs longer than the ESP allows, make it non-blocking and let it install after the desktop arrives.",
-            "Verify the app's detection rule matches after install — an app that installs but fails detection times out the ESP on every device (see ANALYZE-APP-013).",
-            "If a subcategory such as Certificates is reported under '{{failedSubcategory}}', confirm the certificate/connector actually delivers — 'Continue anyway' hides a missing certificate, it does not fix it."
+            "Look at how long `{{appName}}` takes on a device that completes: if it legitimately needs longer than the ESP allows, make it non-blocking (remove it from 'block device use until these required apps are installed') and let it install after the desktop arrives.",
+            "If the app must stay blocking, raise the ESP setting 'Show error when installation takes longer than' (configured at {{espSyncFailureTimeoutMinutes}} min) — a limit, not a target; it only helps when the app reliably finishes within the new value.",
+            "Check the app's dependencies and install order: a blocking app waiting on a large dependency download (Delivery Optimization, proxy throughput) is the usual reason it never finishes in time.",
+            "If the ESP reported a non-Apps subcategory under '{{failedSubcategory}}', confirm the certificate/connector actually delivers — 'Continue anyway' hides a missing certificate, it does not fix it."
           ]
         }
       ],
@@ -2794,6 +3170,7 @@
       "description": "Detects when a certificate with the configured subject is missing from the local machine personal store (LocalMachine\\My). Requires the gather rule GATHER-ID-002 (machine cert store inventory) to be enabled — the check runs against its gather_machine_cert_store output. A missing certificate may indicate that MDM enrollment certificate provisioning or SCEP certificate deployment failed.",
       "severity": "warning",
       "category": "identity",
+      "author": "Community",
       "isCommunity": true,
       "enabled": false,
       "evaluateOn": [
@@ -3233,10 +3610,10 @@
     {
       "ruleId": "ANALYZE-OFFICE-001",
       "title": "Microsoft 365 Apps Install Failed",
-      "description": "Detects when the Microsoft 365 Apps (Office Click-to-Run) background install did not reach completion. The V2 OfficeInstallDetector watches the C2R client directly (registry + process) and emits office_install_failed when the install scenario was abandoned (worker gone and streaming never finished) or a C2R failure code was observed. This catches Office failures that the Intune integrated app type hides, because IME reports the app done within 1-2 minutes while C2R keeps installing in the background.",
+      "description": "Detects when the Microsoft 365 Apps (Office Click-to-Run) install failed. The V2 OfficeInstallDetector watches the C2R client directly (registry, Delivery Optimization, process) and emits office_install_failed when the C2R INSTALL scenario records an error code. Completion is proven by the core Office binaries on disk; an install window that closes without that proof ends silently, never as a failure. This catches Office failures the deployment status hides: the Intune built-in app type is marked done once the configuration is delivered, and a Win32 or RealmJoin package once its installer exits, while C2R keeps installing in the background.",
       "severity": "warning",
       "category": "apps",
-      "version": "1.1.0",
+      "version": "1.1.1",
       "enabled": true,
       "evaluateOn": [
         "enrollment_end",
@@ -3270,12 +3647,12 @@
         }
       ],
       "confidenceThreshold": 40,
-      "explanation": "The Microsoft 365 Apps (Office Click-to-Run) install did not finish.\n\nThe OfficeInstallDetector watches the C2R client directly and reports the real background install lifecycle. The Intune \"integrated\" Microsoft 365 Apps app type only pushes the configuration XML and starts the C2R bootstrapper, so IME marks the app done within 1-2 minutes while C2R keeps streaming and laying down the product for several more minutes. This event means C2R activity ended (the OfficeC2RClient worker exited and the install scenario cleared) without the StreamingFinished flag being set, or a C2R failure code was observed.\n\nReview the office_install_failed event payload: `products`, `channel`, `phase`, `streamingFinished`, `errorCode` (best-effort — may be empty) and `durationSeconds`.",
+      "explanation": "The Microsoft 365 Apps (Office Click-to-Run) install failed.\n\nThe OfficeInstallDetector watches the C2R client directly and reports the real install lifecycle, however it was started. The Intune built-in Microsoft 365 Apps app type delivers the configuration through the Office CSP and lets the device start C2R; a Win32 or RealmJoin package runs the Office Deployment Tool. Either way the deployment is marked done before C2R has finished laying down the product. This event means C2R recorded an error code in its INSTALL scenario before the core Office apps were on disk.\n\nReview the office_install_failed event payload: `products`, `channel`, `errorCode`, `errorSource` (the C2R registry value that carried the code) and `durationSeconds`.",
       "remediation": [
         {
           "title": "Investigate the Office C2R install failure",
           "steps": [
-            "Open the office_install_failed event and review products, channel, phase, streamingFinished and errorCode",
+            "Open the office_install_failed event and review products, channel, errorCode and errorSource",
             "Check the Click-to-Run logs on the device (%windir%\\Temp and %temp%, files named <MachineName>-yyyymmdd-nnnn.log) for the failing operation",
             "Verify the device had network reachability to the Office CDN / Microsoft Connected Cache during the enrollment window",
             "Confirm the Intune Microsoft 365 Apps app configuration (products, channel, architecture) matches what the device can install",

rules/dist/ime-log-patterns.json

@@ -34,6 +34,14 @@
       "description": "Captures the exit code of a health-script execution. Feeds the early-signal slot consumed by HS-COMPLIANCE so the user sees the real exit code (not just the inferred 0/1) before HS-NEW-RESULT arrives.",
       "enabled": true
     },
+    {
+      "patternId": "HS-INVOCATION",
+      "category": "always",
+      "pattern": "^\"[^\"]{0,260}\\\\agentexecutor\\.exe\"\\s+-(?<kind>remediationScript)\\s",
+      "action": "agentInvocationArgument",
+      "description": "The IME service's command line for a health-script executor, written by the health-script worker to IntuneManagementExtension.log and HealthScripts.log right before 'Launch powershell executor in ... session'. Opens an invocation that owns nothing, so the launch line the same worker writes next never sets the context of the platform script whose run is in flight in the IME log. The platform-script command line ('-powershell') does not match.",
+      "enabled": true
+    },
     {
       "patternId": "HS-NEW-RESULT",
       "category": "always",
@@ -195,7 +203,7 @@
       "category": "currentPhase",
       "pattern": "^\\[DO TEL\\] = (?<doTelJson>\\{.*\\})",
       "action": "updateDoTelemetry",
-      "description": "Captures Delivery Optimization telemetry JSON after a DO download completes. Contains file size, peer caching stats, download mode, and duration. IME removed the [DO TEL] emitter in 1.104 (absent in 1.104.102.0 and 1.105.103.0 decompiles, present in 1.97.107.0); kept while 1.101/1.103 devices are in the fleet — retire once those versions are gone.",
+      "description": "Captures Delivery Optimization telemetry JSON after a DO download completes. Contains file size, peer caching stats, download mode, and duration. IME removed the [DO TEL] emitter in 1.104 (absent from the 1.104.102.0 and 1.105.103.0 builds, present in 1.97.107.0); kept while 1.101/1.103 devices are in the fleet — retire once those versions are gone.",
       "enabled": true
     },
     {
@@ -576,7 +584,7 @@
       "category": "always",
       "pattern": "^Failed to get AAD token\\..*?errorCode = (?<errorCode>.*?)$",
       "action": "imeTokenFailure",
-      "description": "IME token acquisition failure ('Failed to get AAD token. len = N using client id ... and resource id ..., errorCode = N', IntuneTokenManager, IntuneManagementExtension.log). This line appears ROUTINELY during the device phase (no user token exists yet), so the agent holds the failure pending: any IME-TOKEN-SUCCESS match clears it, and the ime_token_failure Warning fires only when no success follows for the whole 30-min grace window (then deduped to one Warning per distinct errorCode). A genuine auth outage (WAM broken, conditional access, network) runs long enough to hit the window. Verified against IME 1.97 and 1.104 decompiled sources.",
+      "description": "IME token acquisition failure ('Failed to get AAD token. len = N using client id ... and resource id ..., errorCode = N', IntuneTokenManager, IntuneManagementExtension.log). This line appears ROUTINELY during the device phase (no user token exists yet), so the agent holds the failure pending: any IME-TOKEN-SUCCESS match clears it, and the ime_token_failure Warning fires only when no success follows for the whole 30-min grace window (then deduped to one Warning per distinct errorCode). A genuine auth outage (WAM broken, conditional access, network) runs long enough to hit the window. Verified against IME 1.97 and 1.104.",
       "enabled": true
     },
     {
@@ -646,6 +654,22 @@
       "description": "Detects WinGet app installation progress with Operation Phase = Installing (format variant 2).",
       "enabled": true
     },
+    {
+      "patternId": "PS-AGENT-ARG",
+      "category": "always",
+      "pattern": "^Adding argument (?<kind>[A-Za-z0-9]+) with value ",
+      "action": "agentInvocationArgument",
+      "description": "The first argument line of every AgentExecutor.exe invocation (powershell, remediationScript, detectionScript, requirementScript, ...). Opens the invocation that owns the policyId-less exit/output lines following it in AgentExecutor.log; PS-AGENT-SCRIPT-START upgrades a powershell invocation to its platform script. Also keeps the tracker's overwrite check active while the invocation runs.",
+      "enabled": true
+    },
+    {
+      "patternId": "PS-AGENT-COMPLETED",
+      "category": "always",
+      "pattern": "^Agent executor completed\\.",
+      "action": "agentExecutorCompleted",
+      "description": "Last line of an AgentExecutor.exe invocation. Closes the invocation's ownership of the exit/output lines in AgentExecutor.log and triggers the tracker's overwrite check: the executor wrote its end block at its own stream position, which may lie behind the tracker's bookmark when another process appended meanwhile.",
+      "enabled": true
+    },
     {
       "patternId": "PS-AGENT-ERROR",
       "category": "always",
@@ -708,14 +732,6 @@
       "description": "Captures whether a PowerShell script runs in machine (System) or user session context.",
       "enabled": true
     },
-    {
-      "patternId": "PS-SCRIPT-EXITCODE",
-      "category": "always",
-      "pattern": "^Powershell execution is done, exitCode = (?<exitCode>-?\\d+)",
-      "action": "scriptExitCode",
-      "description": "Captures the PowerShell exit code when script execution completes in the IME log.",
-      "enabled": true
-    },
     {
       "patternId": "PS-SCRIPT-GENERATED",
       "category": "always",

rules/guardrails.json

@@ -94,7 +94,11 @@
     "C:\\Windows\\Panther",
     "C:\\Windows\\SetupDiag",
     "C:\\ProgramData\\Microsoft\\DiagnosticLogCSP",
-    "C:\\Windows\\SoftwareDistribution\\ReportingEvents.log"
+    "C:\\Windows\\SoftwareDistribution\\ReportingEvents.log",
+    "C:\\ProgramData\\RealmJoin\\choco\\logs"
+  ],
+  "userProfileFilePrefixes": [
+    "AppData\\Local\\RealmJoin"
   ],
   "wmiQueryPrefixes": [
     "SELECT * FROM Win32_OperatingSystem",
@@ -296,6 +300,7 @@
     "script_completed",
     "script_failed",
     "script_timeout_suspected",
+    "script_recurrence_summary",
     "esp_phase_changed",
     "ime_agent_version",
     "ime_token_failure",

rules/ime-log-patterns/HS-INVOCATION.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "../schema/ime-log-pattern.schema.json",
+  "patternId": "HS-INVOCATION",
+  "category": "always",
+  "pattern": "^\"[^\"]{0,260}\\\\agentexecutor\\.exe\"\\s+-(?<kind>remediationScript)\\s",
+  "action": "agentInvocationArgument",
+  "description": "The IME service's command line for a health-script executor, written by the health-script worker to IntuneManagementExtension.log and HealthScripts.log right before 'Launch powershell executor in ... session'. Opens an invocation that owns nothing, so the launch line the same worker writes next never sets the context of the platform script whose run is in flight in the IME log. The platform-script command line ('-powershell') does not match.",
+  "enabled": true
+}

rules/ime-log-patterns/IME-DO-TEL.json

@@ -4,6 +4,6 @@
   "category": "currentPhase",
   "pattern": "^\\[DO TEL\\] = (?<doTelJson>\\{.*\\})",
   "action": "updateDoTelemetry",
-  "description": "Captures Delivery Optimization telemetry JSON after a DO download completes. Contains file size, peer caching stats, download mode, and duration. IME removed the [DO TEL] emitter in 1.104 (absent in 1.104.102.0 and 1.105.103.0 decompiles, present in 1.97.107.0); kept while 1.101/1.103 devices are in the fleet — retire once those versions are gone.",
+  "description": "Captures Delivery Optimization telemetry JSON after a DO download completes. Contains file size, peer caching stats, download mode, and duration. IME removed the [DO TEL] emitter in 1.104 (absent from the 1.104.102.0 and 1.105.103.0 builds, present in 1.97.107.0); kept while 1.101/1.103 devices are in the fleet — retire once those versions are gone.",
   "enabled": true
 }

rules/ime-log-patterns/IME-TOKEN-FAILURE.json

@@ -4,6 +4,6 @@
   "category": "always",
   "pattern": "^Failed to get AAD token\\..*?errorCode = (?<errorCode>.*?)$",
   "action": "imeTokenFailure",
-  "description": "IME token acquisition failure ('Failed to get AAD token. len = N using client id ... and resource id ..., errorCode = N', IntuneTokenManager, IntuneManagementExtension.log). This line appears ROUTINELY during the device phase (no user token exists yet), so the agent holds the failure pending: any IME-TOKEN-SUCCESS match clears it, and the ime_token_failure Warning fires only when no success follows for the whole 30-min grace window (then deduped to one Warning per distinct errorCode). A genuine auth outage (WAM broken, conditional access, network) runs long enough to hit the window. Verified against IME 1.97 and 1.104 decompiled sources.",
+  "description": "IME token acquisition failure ('Failed to get AAD token. len = N using client id ... and resource id ..., errorCode = N', IntuneTokenManager, IntuneManagementExtension.log). This line appears ROUTINELY during the device phase (no user token exists yet), so the agent holds the failure pending: any IME-TOKEN-SUCCESS match clears it, and the ime_token_failure Warning fires only when no success follows for the whole 30-min grace window (then deduped to one Warning per distinct errorCode). A genuine auth outage (WAM broken, conditional access, network) runs long enough to hit the window. Verified against IME 1.97 and 1.104.",
   "enabled": true
 }

rules/ime-log-patterns/PS-AGENT-ARG.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "../schema/ime-log-pattern.schema.json",
+  "patternId": "PS-AGENT-ARG",
+  "category": "always",
+  "pattern": "^Adding argument (?<kind>[A-Za-z0-9]+) with value ",
+  "action": "agentInvocationArgument",
+  "description": "The first argument line of every AgentExecutor.exe invocation (powershell, remediationScript, detectionScript, requirementScript, ...). Opens the invocation that owns the policyId-less exit/output lines following it in AgentExecutor.log; PS-AGENT-SCRIPT-START upgrades a powershell invocation to its platform script. Also keeps the tracker's overwrite check active while the invocation runs.",
+  "enabled": true
+}

rules/ime-log-patterns/PS-AGENT-COMPLETED.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "../schema/ime-log-pattern.schema.json",
+  "patternId": "PS-AGENT-COMPLETED",
+  "category": "always",
+  "pattern": "^Agent executor completed\\.",
+  "action": "agentExecutorCompleted",
+  "description": "Last line of an AgentExecutor.exe invocation. Closes the invocation's ownership of the exit/output lines in AgentExecutor.log and triggers the tracker's overwrite check: the executor wrote its end block at its own stream position, which may lie behind the tracker's bookmark when another process appended meanwhile.",
+  "enabled": true
+}

rules/ime-log-patterns/PS-SCRIPT-EXITCODE.json

@@ -1,9 +0,0 @@
-{
-  "$schema": "../schema/ime-log-pattern.schema.json",
-  "patternId": "PS-SCRIPT-EXITCODE",
-  "category": "always",
-  "pattern": "^Powershell execution is done, exitCode = (?<exitCode>-?\\d+)",
-  "action": "scriptExitCode",
-  "description": "Captures the PowerShell exit code when script execution completes in the IME log.",
-  "enabled": true
-}

rules/schema/analyze-rule.schema.json

@@ -190,7 +190,7 @@
         },
         "operator": {
           "type": "string",
-          "description": "Comparison operator.",
+          "description": "Comparison operator. exists/not_exists with a dataField test whether ANY event of the type carries a non-empty value at that field: not_exists matches when no event does — including when the event type is absent altogether — so a rule can gate on a missing field (e.g. an ESP failure without an HRESULT). Without a dataField they test only the presence of the event type.",
           "enum": ["equals", "not_equals", "contains", "not_contains", "regex", "not_regex", "gt", "lt", "gte", "lte", "exists", "not_exists", "count_gte", "count_per_group_gte", "in", "not_in"]
         },
         "value": {

rules/schema/gather-rule.schema.json

@@ -114,6 +114,11 @@
           "description": "Emit behavior: \"always\" (default — emit on every collection) or \"on_change\" (poll on the trigger cadence but emit only when the collected result changes; the first in-scope result always emits).",
           "enum": ["always", "on_change"]
         },
+        "enrichErrorCodes": {
+          "type": "boolean",
+          "description": "Opt-in: let the backend explain error-code fields in this rule's output (exitCode, errorCode, hresult, ...) with the Windows/MSI/Intune error-code catalog, attaching the same *Info siblings built-in events get. Default false because gather-rule codes usually come from third-party logs or commands (HP Image Assistant, Dell Command Update, custom scripts) with their own exit-code numbering, where the catalog meaning would be wrong. Enable only when the parsed source really uses Windows codes (e.g. an msiexec or IME log).",
+          "default": false
+        },
         "outputEventType": {
           "type": "string",
           "description": "EventType for the emitted event (e.g., \"gather_proxy_settings\")."

rules/schema/guardrails.schema.json

@@ -8,6 +8,16 @@
     "$schema": { "type": "string" },
     "registryPrefixes": { "$ref": "#/$defs/categorizedList" },
     "filePrefixes": { "$ref": "#/$defs/stringList" },
+    "userProfileFilePrefixes": {
+      "description": "Folders under the signed-in user's profile that file collectors and diagnostics paths may read, RELATIVE to the profile root (e.g. \"AppData\\\\Local\\\\Vendor\"). Resolved against %LOGGED_ON_USER_PROFILE% at match time. Entries outside AppData\\Local / AppData\\Roaming are dropped at load: the C:\\Users hard block never admits them, so this list can only ever narrow what the block's exception already permits.",
+      "type": "array",
+      "items": {
+        "allOf": [
+          { "$ref": "#/$defs/safeString" },
+          { "pattern": "^AppData\\\\(Local|Roaming)(\\\\|$)" }
+        ]
+      }
+    },
     "wmiQueryPrefixes": { "$ref": "#/$defs/stringList" },
     "eventLogChannels": { "$ref": "#/$defs/categorizedList" },
     "blockedEventLogChannels": { "$ref": "#/$defs/stringList" },

rules/schema/ime-log-pattern.schema.json

@@ -71,6 +71,8 @@
             "scriptOutput",
             "scriptCompleted",
             "resetPlatformScriptContext",
+            "agentInvocationArgument",
+            "agentExecutorCompleted",
             "healthScriptResult",
             "healthScriptDetectionResult",
             "captureExitCode",

rules/scripts/combine.js

@@ -208,6 +208,14 @@ export const ALLOWED_FILE_PREFIXES: readonly string[] = [
 ${flatArray(guardrails.filePrefixes)}
 ];
 
+// Folders under the signed-in user's profile, RELATIVE to the profile root. The agent
+// resolves %LOGGED_ON_USER_PROFILE% at runtime; the portal validates against a placeholder
+// profile. These cannot live in ALLOWED_FILE_PREFIXES — that list is matched literally
+// against the already-expanded path, where the user name is unknown at authoring time.
+export const USER_PROFILE_FILE_PREFIXES: readonly string[] = [
+${flatArray(guardrails.userProfileFilePrefixes ?? [])}
+];
+
 export const ALLOWED_WMI_QUERY_PREFIXES: readonly string[] = [
 ${flatArray(guardrails.wmiQueryPrefixes)}
 ];

rules/scripts/package-lock.json

@@ -0,0 +1,90 @@
+{
+  "name": "autopilot-monitor-rules-tooling",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "autopilot-monitor-rules-tooling",
+      "devDependencies": {
+        "ajv": "8.20.0",
+        "ajv-formats": "3.0.1"
+      }
+    },
+    "node_modules/ajv": {
+      "version": "8.20.0",
+      "resolved": "https://registry.npmjs.org/ajv/-/ajv-8.20.0.tgz",
+      "integrity": "sha512-Thbli+OlOj+iMPYFBVBfJ3OmCAnaSyNn4M1vz9T6Gka5Jt9ba/HIR56joy65tY6kx/FCF5VXNB819Y7/GUrBGA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "fast-deep-equal": "^3.1.3",
+        "fast-uri": "^3.0.1",
+        "json-schema-traverse": "^1.0.0",
+        "require-from-string": "^2.0.2"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/epoberezkin"
+      }
+    },
+    "node_modules/ajv-formats": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/ajv-formats/-/ajv-formats-3.0.1.tgz",
+      "integrity": "sha512-8iUql50EUR+uUcdRQ3HDqa6EVyo3docL8g5WJ3FNcWmu62IbkGUue/pEyLBW8VGKKucTPgqeks4fIU1DA4yowQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "ajv": "^8.0.0"
+      },
+      "peerDependencies": {
+        "ajv": "^8.0.0"
+      },
+      "peerDependenciesMeta": {
+        "ajv": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/fast-deep-equal": {
+      "version": "3.1.3",
+      "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",
+      "integrity": "sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/fast-uri": {
+      "version": "3.1.8",
+      "resolved": "https://registry.npmjs.org/fast-uri/-/fast-uri-3.1.8.tgz",
+      "integrity": "sha512-GZMtZUTNRpOVIECoXwLNZS5xUGE+mVNbTB8h/7Rwh2TFWcBQiPzTgyZi05BF9UMZKkLJv8XBRJTlU7zg8+ZfMg==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fastify"
+        },
+        {
+          "type": "opencollective",
+          "url": "https://opencollective.com/fastify"
+        }
+      ],
+      "license": "BSD-3-Clause"
+    },
+    "node_modules/json-schema-traverse": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/json-schema-traverse/-/json-schema-traverse-1.0.0.tgz",
+      "integrity": "sha512-NM8/P9n3XjXhIZn1lLhkFaACTOURQXjWhV4BA/RnOv8xvgqtqpAX9IO4mRQxSx1Rlo4tqzeqb0sOlruaOy3dug==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/require-from-string": {
+      "version": "2.0.2",
+      "resolved": "https://registry.npmjs.org/require-from-string/-/require-from-string-2.0.2.tgz",
+      "integrity": "sha512-Xf0nWe6RseziFMu+Ap9biiUbmplq6S9/p+7w7YXP/JBHhrUDDUhwa+vANyubuqfZWTveU//DYVGsDG7RKL/vEw==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    }
+  }
+}

rules/scripts/package.json

@@ -0,0 +1,9 @@
+{
+  "name": "autopilot-monitor-rules-tooling",
+  "private": true,
+  "description": "Validator tooling for rules/ - combine-rules.yml installs from the lockfile so nothing unpinned reaches a job that pushes to main.",
+  "devDependencies": {
+    "ajv": "8.20.0",
+    "ajv-formats": "3.0.1"
+  }
+}

rules/scripts/validate.js

@@ -0,0 +1,63 @@
+#!/usr/bin/env node
+/**
+ * Validates every rule file and rules/guardrails.json against its JSON Schema
+ * (draft 2020-12). combine-rules.yml runs this before combine.js; any invalid
+ * file fails the run with exit code 1.
+ *
+ * Run: node rules/scripts/validate.js   (after `npm ci --ignore-scripts` in rules/scripts)
+ */
+
+const fs = require('fs');
+const path = require('path');
+const Ajv2020 = require('ajv/dist/2020');
+const addFormats = require('ajv-formats');
+
+const rulesRoot = path.resolve(__dirname, '..');
+
+const jsonFilesIn = (dir) =>
+  fs.readdirSync(path.join(rulesRoot, dir)).filter(f => f.endsWith('.json')).sort().map(f => `${dir}/${f}`);
+
+const sets = [
+  { schema: 'gather-rule.schema.json', files: jsonFilesIn('gather') },
+  { schema: 'analyze-rule.schema.json', files: jsonFilesIn('analyze') },
+  { schema: 'ime-log-pattern.schema.json', files: jsonFilesIn('ime-log-patterns') },
+  // guardrails.json values are baked verbatim into generated TypeScript that is
+  // auto-committed to main and shipped to the portal - the schema forbids control
+  // and line-terminator characters so a "data" PR can never become code.
+  { schema: 'guardrails.schema.json', files: ['guardrails.json'] }
+];
+
+const ajv = new Ajv2020({ allErrors: true });
+addFormats(ajv);
+
+let invalid = 0;
+
+for (const set of sets) {
+  const validate = ajv.compile(JSON.parse(fs.readFileSync(path.join(rulesRoot, 'schema', set.schema), 'utf8')));
+
+  for (const file of set.files) {
+    let data;
+    try {
+      data = JSON.parse(fs.readFileSync(path.join(rulesRoot, file), 'utf8'));
+    } catch (err) {
+      invalid++;
+      console.error(`INVALID rules/${file}: ${err.message}`);
+      continue;
+    }
+
+    if (!validate(data)) {
+      invalid++;
+      console.error(`INVALID rules/${file}`);
+      for (const e of validate.errors) {
+        console.error(`  ${e.instancePath || '(root)'} ${e.message} ${JSON.stringify(e.params)}`);
+      }
+    }
+  }
+
+  console.log(`${set.schema}: ${set.files.length} files checked`);
+}
+
+if (invalid > 0) {
+  console.error(`ERROR: ${invalid} file(s) failed schema validation`);
+  process.exit(1);
+}

scripts/Bootstrap/Install-AutopilotMonitor.Tests.ps1

@@ -14,6 +14,22 @@
 BeforeAll {
     . (Join-Path $PSScriptRoot 'Install-AutopilotMonitor.ps1')
 
+    function New-FakeSignature {
+        param([string]$Status, [string]$Subject)
+        $cert = if ($Subject) {
+            [pscustomobject]@{ Subject = $Subject; Thumbprint = '0123456789ABCDEF' }
+        } else { $null }
+        return [pscustomobject]@{ Status = $Status; SignerCertificate = $cert }
+    }
+
+    function New-FakePayload {
+        param([string[]]$Files)
+        $dir = Join-Path $TestDrive ([guid]::NewGuid().ToString())
+        New-Item -ItemType Directory -Path $dir -Force | Out-Null
+        foreach ($f in $Files) { Set-Content -Path (Join-Path $dir $f) -Value 'x' }
+        return $dir
+    }
+
     function New-FakeProfile {
         param([string]$Name, [double]$AgeMinutes)
         $p = Join-Path $TestDrive $Name
@@ -305,3 +321,93 @@ Describe 'logging purity' {
         Get-Content $LogFile -Raw | Should -Match 'SKIP: Agent was previously deployed'
     }
 }
+
+Describe 'Get-UnverifiedAgentBinaries' {
+    # The publisher gate on the extracted payload. What matters is the DECISION: which
+    # payload is accepted, which is refused, and which files are looked at at all.
+    BeforeEach {
+        Mock Write-Log { }
+        $script:ours = 'CN=glueckkanja AG, O=glueckkanja AG, C=DE'
+    }
+
+    It 'accepts a payload where every binary of ours is validly signed by us' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe', 'AutopilotMonitor.Shared.dll')
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'Valid' -Subject $script:ours }
+        Get-UnverifiedAgentBinaries -Path $dir | Should -BeNullOrEmpty
+    }
+
+    It 'checks the binaries we author and leaves third-party assemblies alone' {
+        $dir = New-FakePayload -Files @(
+            'AutopilotMonitor.Agent.exe',
+            'AutopilotMonitor.Agent.exe.config',
+            'AutopilotMonitor.Shared.dll',
+            'Newtonsoft.Json.dll',
+            'System.Management.Automation.dll'
+        )
+        $script:checked = @()
+        Mock Get-AuthenticodeSignature {
+            $script:checked += (Split-Path $FilePath -Leaf)
+            New-FakeSignature -Status 'Valid' -Subject $script:ours
+        }
+
+        Get-UnverifiedAgentBinaries -Path $dir | Should -BeNullOrEmpty
+        $script:checked | Should -Be @('AutopilotMonitor.Agent.exe', 'AutopilotMonitor.Shared.dll')
+    }
+
+    It 'refuses an unsigned agent executable' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe')
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'NotSigned' -Subject $null }
+        (Get-UnverifiedAgentBinaries -Path $dir).Count | Should -Be 1
+    }
+
+    It 'refuses a tampered binary (hash mismatch)' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe')
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'HashMismatch' -Subject $script:ours }
+        (Get-UnverifiedAgentBinaries -Path $dir).Count | Should -Be 1
+    }
+
+    It 'refuses a signature whose chain does not validate' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe')
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'UnknownError' -Subject $script:ours }
+        (Get-UnverifiedAgentBinaries -Path $dir).Count | Should -Be 1
+    }
+
+    It 'refuses a validly signed binary from a different publisher' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe')
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'Valid' -Subject 'CN=Somebody Else, O=Somebody Else Ltd, C=US' }
+        (Get-UnverifiedAgentBinaries -Path $dir).Count | Should -Be 1
+    }
+
+    It 'refuses the whole payload when a single DLL of ours is swapped' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe', 'AutopilotMonitor.Shared.dll')
+        Mock Get-AuthenticodeSignature {
+            if ((Split-Path $FilePath -Leaf) -eq 'AutopilotMonitor.Shared.dll') {
+                New-FakeSignature -Status 'Valid' -Subject 'CN=Somebody Else, O=Somebody Else Ltd, C=US'
+            } else {
+                New-FakeSignature -Status 'Valid' -Subject $script:ours
+            }
+        }
+        $rejected = Get-UnverifiedAgentBinaries -Path $dir
+        $rejected.Count | Should -Be 1
+        $rejected[0] | Should -BeLike 'AutopilotMonitor.Shared.dll*'
+    }
+
+    It 'refuses when the signature check itself throws' {
+        $dir = New-FakePayload -Files @('AutopilotMonitor.Agent.exe')
+        Mock Get-AuthenticodeSignature { throw 'access denied' }
+        (Get-UnverifiedAgentBinaries -Path $dir).Count | Should -Be 1
+    }
+
+    It 'refuses an empty payload instead of passing it' {
+        $dir = New-FakePayload -Files @('Newtonsoft.Json.dll')
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'Valid' -Subject $script:ours }
+        (Get-UnverifiedAgentBinaries -Path $dir).Count | Should -Be 1
+    }
+}
+
+Describe 'publisher pin' {
+    It 'pins the expected publisher by subject, not by thumbprint' {
+        $ExpectedPublisher | Should -Be '*O=glueckkanja AG*'
+        $ExpectedPublisher | Should -Not -Match '^[0-9A-Fa-f]{40}$'
+    }
+}

scripts/Bootstrap/Install-AutopilotMonitor.ps1

@@ -12,8 +12,9 @@
       2. Downloads the monitoring agent ZIP from Azure Blob Storage
       3. Verifies integrity via SHA-256 hash from the version manifest (mandatory)
       4. Extracts the agent into %ProgramData%\AutopilotMonitor\Agent
-      5. Runs the agent in --install mode (registers Scheduled Task, spawns the runtime)
-      6. Verifies the runtime process actually launched
+      5. Verifies the Authenticode signature and publisher of every binary we author
+      6. Runs the agent in --install mode (registers Scheduled Task, spawns the runtime)
+      7. Verifies the runtime process actually launched
     Agent self-destructs when enrollment completes.
 
     Relax flow (guards 2+3): a real user profile (or a real LastLoggedOnUser)
@@ -76,6 +77,11 @@
       PowerShell 5.1 (IME) reads scripts without BOM as ANSI, corrupting multi-byte chars.
 
 .CHANGELOG
+    2026-09-08  v2.5  Publisher gate: every AutopilotMonitor binary in the extracted
+                      payload must carry a valid Authenticode signature from the
+                      expected publisher before --install runs. The SHA-256 manifest
+                      check stays and is unchanged; it proves the bytes, the signature
+                      proves the author.
     2026-08-08  v2.3  Windows 365 Cloud PC support: a positively identified Cloud PC
                       (Windows365 registry key AND CloudManagedDesktopExtension
                       service) now triggers the guard 2+3 relax alongside OOBE
@@ -128,7 +134,12 @@ param(
 )
 
 # Script version (bump on meaningful changes; see .CHANGELOG above)
-$ScriptVersion = "2.4"
+$ScriptVersion = "2.5"
+
+# The publisher every binary we author must carry. A -like pattern on the subject, NOT a
+# thumbprint: certificates are renewed, deployed copies of this script are not. Same value
+# the loader pins for this script.
+$ExpectedPublisher = "*O=glueckkanja AG*"
 
 # Configuration - Everything in ProgramData for easy cleanup
 $AgentBasePath = "$env:ProgramData\AutopilotMonitor"
@@ -329,6 +340,56 @@ function Get-BootstrapDecision {
     return [pscustomobject]@{ Install = $true; ReasonCode = $null; RelaxActive = $relax.Active }
 }
 
+# Returns the list of reasons why the extracted payload is not ours; an empty result means
+# every binary we author carries a valid Authenticode signature from the expected publisher.
+# Third-party assemblies keep their own publisher's signature and are not checked here.
+# Any error is a rejection: an unreadable signature is an unverified binary.
+function Get-UnverifiedAgentBinaries {
+    param([string]$Path)
+
+    $rejected = @()
+    $ourBinaries = @(
+        Get-ChildItem -Path $Path -Filter 'AutopilotMonitor.*' -File -ErrorAction SilentlyContinue |
+            Where-Object { $_.Extension -in @('.exe', '.dll') }
+    )
+
+    # An empty set is a rejection, not a pass: it means the extraction produced nothing we
+    # recognise, and the alternative would be a gate that silently approves an empty folder.
+    # The comma keeps a single rejection an ARRAY: PowerShell unrolls a one-element result to
+    # a bare string, and the caller reads .Count and indexes into it.
+    if ($ourBinaries.Count -eq 0) {
+        return , @("no AutopilotMonitor binaries found in $Path")
+    }
+
+    foreach ($binary in $ourBinaries) {
+        try {
+            $sig = Get-AuthenticodeSignature -FilePath $binary.FullName -ErrorAction Stop
+        }
+        catch {
+            $rejected += "$($binary.Name): signature check failed to run ($($_.Exception.Message))"
+            continue
+        }
+
+        if ($null -eq $sig) {
+            $rejected += "$($binary.Name): signature check returned nothing"
+            continue
+        }
+
+        $subject = if ($sig.SignerCertificate) { $sig.SignerCertificate.Subject } else { '<unsigned>' }
+
+        if ($sig.Status -ne 'Valid') {
+            $rejected += "$($binary.Name): signature status $($sig.Status)"
+            continue
+        }
+        if ($subject -notlike $ExpectedPublisher) {
+            $rejected += "$($binary.Name): unexpected publisher $subject"
+            continue
+        }
+    }
+
+    return , $rejected
+}
+
 # Main bootstrap flow. Only invoked when the script is run directly (see entry guard
 # at the bottom); never on dot-source.
 function Invoke-Bootstrap {
@@ -445,6 +506,20 @@ function Invoke-Bootstrap {
             }
         }
 
+        # Publisher gate. The SHA-256 above proves the ZIP is the one the manifest names, but
+        # that manifest lives in the same container as the ZIP and cannot outlive a compromise
+        # of the download host. The expected publisher travels inside THIS script, which the
+        # loader verified before running it, so the chain from the file an administrator
+        # assigns to the process that starts here stays publisher-anchored end to end.
+        # Fail-closed, exactly like the hash check: running unverified code as SYSTEM is the
+        # risk being removed.
+        Write-Log "Verifying Authenticode signatures of the agent binaries..."
+        $unverified = Get-UnverifiedAgentBinaries -Path $AgentBinPath
+        if ($unverified.Count -gt 0) {
+            throw "Authenticode verification FAILED ($($unverified -join '; ')). Refusing to run an agent that is not signed by the expected publisher."
+        }
+        Write-Log "Authenticode verification passed (publisher pin: $ExpectedPublisher)"
+
         Write-Log "Calling agent install mode (--install)..."
         & $agentExePath --install
         $installExitCode = $LASTEXITCODE

scripts/Bootstrap/Start-AutopilotMonitor.Tests.ps1

@@ -0,0 +1,147 @@
+# Pester tests (Pester 5+) for the stage-1 loader Start-AutopilotMonitor.ps1.
+#
+# The script under test is dot-sourced; its entry guard prevents the loader from
+# executing, so loading it here is side-effect free. Network and signature checks
+# are mocked -- what is verified is the DECISION: what does the loader accept, what
+# does it refuse, and how often does it retry.
+#
+# Run under Windows PowerShell 5.1 to match the IME runtime:
+#   powershell.exe -NoProfile -Command "& { $c = New-PesterConfiguration; $c.Run.Path = 'scripts\Bootstrap'; $c.Output.Verbosity = 'Detailed'; Invoke-Pester -Configuration $c }"
+#
+# This file MUST remain pure ASCII (PS 5.1 reads BOM-less files as ANSI).
+
+BeforeAll {
+    . (Join-Path $PSScriptRoot 'Start-AutopilotMonitor.ps1')
+
+    function New-FakeSignature {
+        param([string]$Status, [string]$Subject)
+        $cert = if ($Subject) {
+            [pscustomobject]@{ Subject = $Subject; Thumbprint = '0123456789ABCDEF' }
+        } else { $null }
+        return [pscustomobject]@{ Status = $Status; SignerCertificate = $cert }
+    }
+}
+
+Describe 'Test-BootstrapSignature' {
+    BeforeEach {
+        Mock Write-Log { }
+    }
+
+    It 'accepts a valid signature from the expected publisher' {
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'Valid' -Subject 'CN=glueckkanja AG, O=glueckkanja AG, C=DE' }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeTrue
+    }
+
+    # An EV subject is a line of street address and registration numbers; the log gets the CN.
+    It 'logs the signer CN, not the whole subject' {
+        Mock Get-AuthenticodeSignature {
+            New-FakeSignature -Status 'Valid' -Subject 'CN=glueckkanja AG, O=glueckkanja AG, L=Offenbach am Main, C=DE, SERIALNUMBER=HRB 12381'
+        }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeTrue
+        Should -Invoke Write-Log -ParameterFilter { $Message -eq 'Signature status: Valid. Signer: glueckkanja AG' }
+    }
+
+    It 'refuses an unsigned script' {
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'NotSigned' -Subject $null }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeFalse
+    }
+
+    It 'refuses a tampered script (hash mismatch)' {
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'HashMismatch' -Subject 'CN=glueckkanja AG, O=glueckkanja AG, C=DE' }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeFalse
+    }
+
+    It 'refuses a signature whose chain does not validate' {
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'UnknownError' -Subject 'CN=glueckkanja AG, O=glueckkanja AG, C=DE' }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeFalse
+    }
+
+    # The whole point of the pinned publisher: a validly signed script from someone else
+    # is exactly what an attacker with any code-signing certificate can produce.
+    It 'refuses a valid signature from a different publisher' {
+        Mock Get-AuthenticodeSignature { New-FakeSignature -Status 'Valid' -Subject 'CN=Somebody Else, O=Somebody Else Ltd, C=US' }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeFalse
+    }
+
+    It 'refuses when the signature check itself fails' {
+        Mock Get-AuthenticodeSignature { throw 'file not found' }
+        Test-BootstrapSignature -Path 'TestDrive:\x.ps1' | Should -BeFalse
+    }
+}
+
+Describe 'Get-VerifiedBootstrapScript' {
+    BeforeEach {
+        Mock Write-Log { }
+        Mock Start-Sleep { }
+        Mock Invoke-WebRequest { }
+    }
+
+    It 'returns after the first attempt when the download verifies' {
+        Mock Test-BootstrapSignature { $true }
+        Get-VerifiedBootstrapScript -Url 'https://example.invalid/s.ps1' -Destination 'TestDrive:\s.ps1' | Should -BeTrue
+        Should -Invoke Invoke-WebRequest -Times 1 -Exactly
+    }
+
+    It 'gives up after three attempts when verification keeps failing' {
+        Mock Test-BootstrapSignature { $false }
+        Get-VerifiedBootstrapScript -Url 'https://example.invalid/s.ps1' -Destination 'TestDrive:\s.ps1' | Should -BeFalse
+        Should -Invoke Invoke-WebRequest -Times 3 -Exactly
+    }
+
+    # A truncated or proxy-mangled body fails verification, so the retry has to cover the
+    # download AND the check, not just the transport.
+    It 'retries a failed verification and accepts a later attempt' {
+        $script:calls = 0
+        Mock Test-BootstrapSignature { $script:calls++; return ($script:calls -ge 2) }
+        Get-VerifiedBootstrapScript -Url 'https://example.invalid/s.ps1' -Destination 'TestDrive:\s.ps1' | Should -BeTrue
+        Should -Invoke Invoke-WebRequest -Times 2 -Exactly
+    }
+
+    It 'retries a transport failure' {
+        $script:downloads = 0
+        Mock Invoke-WebRequest { $script:downloads++; if ($script:downloads -eq 1) { throw 'connection reset' } }
+        Mock Test-BootstrapSignature { $true }
+        Get-VerifiedBootstrapScript -Url 'https://example.invalid/s.ps1' -Destination 'TestDrive:\s.ps1' | Should -BeTrue
+        Should -Invoke Invoke-WebRequest -Times 2 -Exactly
+    }
+
+    It 'never executes anything when no attempt verifies' {
+        Mock Test-BootstrapSignature { $false }
+        Get-VerifiedBootstrapScript -Url 'https://example.invalid/s.ps1' -Destination 'TestDrive:\s.ps1' | Should -BeFalse
+    }
+}
+
+Describe 'publish contract' {
+    BeforeAll {
+        $script:loaderText = Get-Content (Join-Path $PSScriptRoot 'Start-AutopilotMonitor.ps1') -Raw
+    }
+
+    # Publish-BootstrapScripts.ps1 renders the -Dev loader by substituting this exact
+    # literal and fails the publish when it is gone. Catching that here means the PR fails
+    # instead of the publish.
+    It 'carries the dev-render anchor the publisher substitutes' {
+        $anchor = '$BootstrapUrl = "https://download.autopilotmonitor.com/agent/Install-AutopilotMonitor.ps1"'
+        $script:loaderText.Contains($anchor) | Should -BeTrue
+    }
+
+    # The publisher parses this to write version.json.loaderVersion and to run the
+    # version-bump guard.
+    It 'declares a parsable ScriptVersion' {
+        $script:loaderText -match '\$ScriptVersion\s*=\s*"([\d\.\-a-zA-Z]+)"' | Should -BeTrue
+    }
+
+    It 'pins the expected publisher by subject, not by thumbprint' {
+        $script:loaderText -match '\$ExpectedPublisher\s*=\s*"\*O=' | Should -BeTrue
+    }
+
+    # The bootstrap MSI installs this same file and runs it with -LogFileName so the delivery
+    # channel stays visible in a diagnostics package. Renaming the parameter on either side
+    # would leave the MSI channel silently logging under the wrong name.
+    It 'keeps the -LogFileName contract the bootstrap MSI relies on' {
+        $script:loaderText -match '\[string\]\$LogFileName' | Should -BeTrue
+
+        $wxs = Get-Content (Join-Path $PSScriptRoot '..\..\src\Agent\AutopilotMonitor.BootstrapMsi\Package.wxs') -Raw
+        $wxs.Contains('[INSTALLFOLDER]Start-AutopilotMonitor.ps1') | Should -BeTrue
+        $wxs.Contains('-LogFileName bootstrap-msi.log') | Should -BeTrue
+    }
+}

scripts/Bootstrap/Start-AutopilotMonitor.ps1

@@ -0,0 +1,216 @@
+<#
+.SYNOPSIS
+    Stage 1 of the Autopilot Monitor bootstrap: fetches the current installer and runs it.
+
+.DESCRIPTION
+    This is the file an administrator assigns in Intune, and the same file the bootstrap MSI
+    installs and runs -- one implementation for both delivery channels; the MSI is only the
+    packaging. It carries no enrollment logic at all: it downloads the published
+    Install-AutopilotMonitor.ps1, proves that it was signed by Autopilot Monitor, and runs it
+    in this process.
+
+    Why two stages: the installer holds every guard, relax rule and download path, and those
+    change. Whoever assigns the installer directly has to replace their Intune copy each
+    time; whoever assigns this loader never does, because the part that changes lives on the
+    server. Assigning the installer directly stays supported and unchanged.
+
+    This file is deliberately boring. It is the one piece that cannot be fixed remotely, so
+    it does the least it can: download, verify, invoke, log.
+
+    Verification is by Authenticode publisher, not by hash. A hash oracle would have to be
+    fetched from the same host as the script itself, so it could not survive a compromise of
+    that host, while the expected publisher below travels with this file. It pins the
+    certificate SUBJECT and not a thumbprint, so a certificate renewal does not brick a
+    loader that is already deployed on devices.
+
+    Fail-soft: the loader always exits 0 and never throws into the caller. A device that
+    cannot reach the download endpoint is a device without monitoring, never a failed
+    enrollment step. Verification failures are the same: nothing runs, and the reason is in
+    the log. Refusing to execute unverified code as SYSTEM is the point of this file.
+
+    This file MUST remain pure ASCII (PS 5.1 reads BOM-less files as ANSI).
+
+.PARAMETER BootstrapUrl
+    Installer URL. Defaults to the published stable installer; the -Dev variant of this
+    loader is rendered from that default at publish time.
+
+.PARAMETER LogFileName
+    Log file inside the agent log directory. The MSI channel passes bootstrap-msi.log so the
+    delivery channel stays visible in a diagnostics package; the diag tooling keys on these
+    names, so do not rename them.
+
+.PARAMETER BootstrapArguments
+    Everything else is passed through to the installer unchanged, so any parameter the
+    installer accepts can be set here without this file knowing about it.
+
+.EXAMPLE
+    .\Start-AutopilotMonitor.ps1
+
+.EXAMPLE
+    .\Start-AutopilotMonitor.ps1 -MaxBootstrapWindowHours 24
+
+.NOTES
+    Author  : Oliver Kieselbach (autopilotmonitor.com)
+    Runtime : Windows PowerShell 5.1, SYSTEM context, during Autopilot enrollment
+
+.CHANGELOG
+    2026-09-08  v1.2  Log the signer CN instead of the full EV subject; the full subject is
+                      logged only when the publisher is why a script was rejected.
+    2026-09-08  v1.1  Also used by the bootstrap MSI, which replaced its own copy of this
+                      logic; -LogFileName keeps the channel visible in diagnostics.
+    2026-09-08  v1.0  Initial version: two-stage bootstrap, publisher-pinned verification.
+#>
+
+[CmdletBinding()]
+param(
+    [Parameter(Mandatory = $false)]
+    [string]$BootstrapUrl = "https://download.autopilotmonitor.com/agent/Install-AutopilotMonitor.ps1",
+
+    [Parameter(Mandatory = $false)]
+    [ValidatePattern('^[A-Za-z0-9._-]+$')]
+    [string]$LogFileName = "bootstrap-loader.log",
+
+    [Parameter(Mandatory = $false, ValueFromRemainingArguments = $true)]
+    [string[]]$BootstrapArguments
+)
+
+# Script version (bump on meaningful changes; see .CHANGELOG above)
+$ScriptVersion = "1.2"
+
+# The publisher every downloaded stage-2 script must carry. A -like pattern on the subject,
+# NOT a thumbprint: certificates are renewed, deployed loaders are not.
+$ExpectedPublisher = "*O=glueckkanja AG*"
+
+$LoaderBasePath = "$env:ProgramData\AutopilotMonitor"
+$LoaderLogPath  = "$LoaderBasePath\Logs"
+$LogFile        = "$LoaderLogPath\$LogFileName"
+$BootstrapPath  = "$LoaderBasePath\Install-AutopilotMonitor.ps1"
+
+$DownloadAttempts = 3
+$RetryDelaySeconds = 10
+
+# Write-Host as well as the file: the Intune script output is what an administrator sees in
+# the portal, the file is what a support case reads.
+function Write-Log {
+    param([string]$Message)
+    $timestamp = Get-Date -Format "yyyy-MM-dd HH:mm:ss"
+    $logMessage = "[$timestamp] $Message"
+    Write-Host $logMessage
+    Add-Content -Path $LogFile -Value $logMessage -ErrorAction SilentlyContinue
+}
+
+# True only when the file is signed, the signature validates against the machine's trust
+# chain, and the signer is us. Any error is a false -- an unreadable signature is an
+# unverified script.
+function Test-BootstrapSignature {
+    param([string]$Path)
+
+    try {
+        $sig = Get-AuthenticodeSignature -FilePath $Path -ErrorAction Stop
+    }
+    catch {
+        Write-Log "Signature check failed to run: $($_.Exception.Message)"
+        return $false
+    }
+
+    if ($null -eq $sig) {
+        Write-Log "Signature check returned nothing."
+        return $false
+    }
+
+    # The full subject of an EV certificate is a line of street address and registration
+    # numbers. The CN answers the only question the log has to answer; the full subject is
+    # logged when it is the reason for a rejection.
+    $subject = if ($sig.SignerCertificate) { $sig.SignerCertificate.Subject } else { "<unsigned>" }
+    $signer = if ($subject -match 'CN=([^,]+)') { $Matches[1] } else { $subject }
+    Write-Log "Signature status: $($sig.Status). Signer: $signer"
+
+    if ($sig.Status -ne 'Valid') {
+        Write-Log "REJECTED: expected signature status 'Valid'."
+        return $false
+    }
+    if ($subject -notlike $ExpectedPublisher) {
+        Write-Log "REJECTED: signer does not match the expected publisher. Full subject: $subject"
+        return $false
+    }
+
+    Write-Log "Signature accepted (thumbprint $($sig.SignerCertificate.Thumbprint))."
+    return $true
+}
+
+# Downloads the installer and returns $true once a downloaded copy passes verification.
+# Verification lives inside the retry loop on purpose: a truncated or proxy-mangled body
+# fails the signature check, and that is worth another attempt.
+function Get-VerifiedBootstrapScript {
+    param([string]$Url, [string]$Destination)
+
+    for ($attempt = 1; $attempt -le $DownloadAttempts; $attempt++) {
+        try {
+            Write-Log "Download attempt $attempt/$DownloadAttempts from $Url"
+            Invoke-WebRequest -Uri $Url -OutFile $Destination -UseBasicParsing -TimeoutSec 60 -ErrorAction Stop
+
+            if (Test-BootstrapSignature -Path $Destination) {
+                return $true
+            }
+        }
+        catch {
+            Write-Log "Download attempt $attempt failed: $($_.Exception.Message)"
+        }
+
+        if ($attempt -lt $DownloadAttempts) {
+            Start-Sleep -Seconds $RetryDelaySeconds
+        }
+    }
+
+    return $false
+}
+
+# Main flow. Only invoked when the script is run directly (see entry guard at the bottom),
+# so the Pester suite can dot-source this file without bootstrapping anything.
+function Start-BootstrapLoader {
+    New-Item -ItemType Directory -Force -Path $LoaderLogPath -ErrorAction SilentlyContinue | Out-Null
+
+    Write-Log "=== Autopilot Monitor bootstrap loader v$ScriptVersion started (user=$env:USERNAME, pid=$PID) ==="
+
+    # PS 5.1 on an OOBE device still defaults to TLS 1.0 for this process.
+    try {
+        [Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointManager]::SecurityProtocol -bor [Net.SecurityProtocolType]::Tls12
+    }
+    catch {
+        Write-Log "INFO: could not raise the TLS protocol: $($_.Exception.Message)"
+    }
+
+    if (-not (Get-VerifiedBootstrapScript -Url $BootstrapUrl -Destination $BootstrapPath)) {
+        Write-Log "No verified installer available after $DownloadAttempts attempt(s). Nothing was executed."
+        return
+    }
+
+    Write-Log "Executing $BootstrapPath"
+
+    # Same process, so the execution policy this loader runs under applies to stage 2 as
+    # well and no second policy decision can strand the installer. Splatting an array of
+    # remaining arguments keeps this file free of any knowledge about the installer's
+    # parameters.
+    $arguments = @()
+    if ($BootstrapArguments) { $arguments = $BootstrapArguments }
+
+    try {
+        & $BootstrapPath @arguments
+        Write-Log "Installer finished (exit code $LASTEXITCODE)."
+    }
+    catch {
+        Write-Log "Installer threw: $($_.Exception.Message)"
+    }
+}
+
+# Entry guard: dot-sourcing (Pester) loads the functions without running the loader.
+if ($MyInvocation.InvocationName -ne '.') {
+    try {
+        Start-BootstrapLoader
+    }
+    catch {
+        # Nothing above should throw; if it does, it must not become a failed Intune script.
+        Write-Log "Loader failed: $($_.Exception.Message)"
+    }
+    exit 0
+}

scripts/CustomerSetup/Grant-AutopilotMonitorAddOn.ps1

@@ -29,10 +29,9 @@
          Cloud PCs are never Autopilot-registered, so this enables agent monitoring
          of Cloud PC first-connect enrollment)
       - IntuneDeviceBinding     -> DeviceManagementManagedDevices.Read.All
-        (cert-to-device binding: verifies that the Intune device id carried in the
-         agent's client certificate is a device THIS tenant actually enrolled --
-         currently a Global-Admin-only preview that records telemetry and does not
-         block enrollment)
+        (Intune Enrollment Validation: accepts devices enrolled in THIS tenant's
+         Intune, matched by the Intune device id in the agent's client certificate,
+         without Autopilot registration, corporate identifier or device association)
       - All                    -> every optional permission above, in one run
         (also works with -Revoke to remove all optional grants at once)
 
@@ -76,15 +75,17 @@
 .NOTES
     Requires:
       - Microsoft.Graph.Authentication PowerShell module (auto-installs if missing).
-      - Sign-in as Global Administrator OR Privileged Role Administrator OR Cloud Application Administrator.
+      - Sign-in as Global Administrator OR Privileged Role Administrator (with PIM, activate the
+        role first). Only these roles may assign Microsoft Graph application permissions;
+        Application Administrator and Cloud Application Administrator are not enough.
+      - The Autopilot Monitor app must be admin-consented in your tenant first
+        (its service principal must exist before grants can be added).
 
     Sign-in behaviour:
       In Azure Cloud Shell the script signs in via the ambient identity endpoint (a delegated
       token for the already-signed-in user) - no device-code prompt, which Conditional Access
       policies commonly block. Outside Cloud Shell it falls back to a normal interactive
       Microsoft Graph sign-in. -TenantId only applies to the interactive fallback.
-      - The Autopilot Monitor app must be admin-consented in your tenant first
-        (its service principal must exist before grants can be added).
 
     After granting:
       The Autopilot Monitor backend may cache an older token for up to ~1 hour. Use the
@@ -140,6 +141,36 @@ if ($PSCmdlet.ParameterSetName -eq 'ByFeatures') {
 # ---- Constants ----
 $MicrosoftGraphAppId = '00000003-0000-0000-c000-000000000000'
 
+# ---- Graph failure details ----
+# Invoke-MgGraphRequest puts only "Response status code does not indicate success: ..." into the
+# exception message. Graph's own error (code + message) is the response body in ErrorDetails,
+# behind the request line, the status line and the headers. Some headers carry JSON themselves
+# (x-ms-ags-diagnostic), so the body is taken from behind the blank line that ends the headers.
+function Get-GraphFailure {
+    param([System.Management.Automation.ErrorRecord]$ErrorRecord)
+
+    $status = 0
+    if ($ErrorRecord.Exception.PSObject.Properties['Response'] -and $ErrorRecord.Exception.Response) {
+        $status = [int]$ErrorRecord.Exception.Response.StatusCode
+    }
+
+    $text = $ErrorRecord.Exception.Message
+    if ($ErrorRecord.ErrorDetails -and $ErrorRecord.ErrorDetails.Message) {
+        $body = ($ErrorRecord.ErrorDetails.Message -split '\r?\n\r?\n', 2)[-1].Trim()
+        if ($body.StartsWith('{')) {
+            try {
+                $graphError = ($body | ConvertFrom-Json).error
+                if ($graphError.code) { $text = "$($graphError.code): $($graphError.message)" }
+            }
+            catch {
+                # Not a Graph JSON body - keep the exception message.
+            }
+        }
+    }
+
+    [pscustomobject]@{ Status = $status; Text = $text }
+}
+
 # ---- Pre-flight: module ----
 if (-not (Get-Module -ListAvailable -Name Microsoft.Graph.Authentication)) {
     Write-Host "[Setup] Microsoft.Graph.Authentication not installed. Installing for current user..." -ForegroundColor Yellow
@@ -189,7 +220,7 @@ Write-Host "[Auth] Granted scopes: $($ctx.Scopes -join ', ')"
 # carries a fixed scope set (incl. Directory.AccessAsUser.All) instead of the requested scopes,
 # and its effective rights follow the signed-in user's directory role.
 if (-not $identityConnected -and -not ($ctx.Scopes -contains 'AppRoleAssignment.ReadWrite.All')) {
-    Write-Warning "Scope 'AppRoleAssignment.ReadWrite.All' was NOT granted. The signed-in user likely lacks the required role (Global Admin / Privileged Role Admin / Cloud App Admin)."
+    Write-Warning "Scope 'AppRoleAssignment.ReadWrite.All' was NOT granted. The signed-in user likely lacks the required role (Global Administrator or Privileged Role Administrator)."
     if (-not $VerifyOnly) { return }
 }
 
@@ -263,6 +294,7 @@ $action = if ($Revoke) { 'Revoke' } else { 'Grant' }
 Write-Host "[4/4] $action mode - processing $($Permissions.Count) permission(s)..." -ForegroundColor Cyan
 
 $results = @()
+$graphForbidden = $false
 foreach ($permName in $Permissions) {
     $appRole = $graphSp.appRoles | Where-Object {
         $_.value -eq $permName -and $_.allowedMemberTypes -contains 'Application'
@@ -289,7 +321,9 @@ foreach ($permName in $Permissions) {
                 $results += [pscustomobject]@{ Permission = $permName; Status = 'Revoked' }
             }
             catch {
-                Write-Warning "  [FAIL]  '$permName' revoke failed: $($_.Exception.Message)"
+                $failure = Get-GraphFailure $_
+                if ($failure.Status -eq 403) { $graphForbidden = $true }
+                Write-Warning "  [FAIL]  '$permName' revoke failed: $($failure.Text)"
                 $results += [pscustomobject]@{ Permission = $permName; Status = 'Failed' }
             }
         }
@@ -316,7 +350,9 @@ foreach ($permName in $Permissions) {
             $results += [pscustomobject]@{ Permission = $permName; Status = 'Granted' }
         }
         catch {
-            Write-Warning "  [FAIL]  '$permName' grant failed: $($_.Exception.Message)"
+            $failure = Get-GraphFailure $_
+            if ($failure.Status -eq 403) { $graphForbidden = $true }
+            Write-Warning "  [FAIL]  '$permName' grant failed: $($failure.Text)"
             $results += [pscustomobject]@{ Permission = $permName; Status = 'Failed' }
         }
     }
@@ -325,6 +361,9 @@ foreach ($permName in $Permissions) {
 Write-Host ""
 Write-Host "=========== Summary ===========" -ForegroundColor Cyan
 $results | Format-Table -AutoSize | Out-Host
+if ($graphForbidden) {
+    Write-Warning "Microsoft Graph refused the change (403): the signed-in account may not manage Microsoft Graph application permissions. Sign in as Global Administrator or Privileged Role Administrator (with PIM, activate the role first) and run the script again."
+}
 Write-Host ""
 Write-Host "Note: token-cached backends may need up to ~1h to see the new permission set." -ForegroundColor Yellow
 Write-Host "      Use 'Refresh permission status' in the admin UI to apply changes immediately." -ForegroundColor Yellow

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Configuration/RemoteConfigServiceRetryTests.cs

@@ -144,7 +144,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Configuration
             Assert.Equal(4, svc.LastFetchAttempts);
         }
 
-        // ── Network-link gate (tenant aebdce78 audit 2026-08-24) ────────────
+        // ── Network-link gate (kiosk-tenant audit 2026-08-24) ────────────
 
         [Fact]
         public async Task FetchConfig_InitialFetch_WaitsForNetworkLink()

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Analyzers/SoftwareInventoryRegistryTextTests.cs

@@ -0,0 +1,31 @@
+#nullable enable
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Analyzers;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Analyzers
+{
+    /// <summary>
+    /// Uninstall-key strings are read the way Windows shows them: up to the first NUL. Installers
+    /// that pad REG_SZ data with NULs otherwise leak them into the normalized vendor/name, which
+    /// the backend turns into a table key.
+    /// </summary>
+    public sealed class SoftwareInventoryRegistryTextTests
+    {
+        [Theory]
+        [InlineData("Contoso Widget", "Contoso Widget")]
+        [InlineData("Contoso Widget\0\0\0\0\0", "Contoso Widget")]
+        [InlineData("Contoso\0stale buffer", "Contoso")]
+        [InlineData("\0\0\0", "")]
+        [InlineData("", "")]
+        public void CutAtNul_KeepsTheTextBeforeTheFirstNul(string raw, string expected)
+        {
+            Assert.Equal(expected, SoftwareInventoryAnalyzer.CutAtNul(raw));
+        }
+
+        [Fact]
+        public void CutAtNul_Null_StaysNull()
+        {
+            Assert.Null(SoftwareInventoryAnalyzer.CutAtNul(null!));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/EspAndHelloTrackerShellCoreFailureInheritanceTests.cs

@@ -0,0 +1,132 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.SignalAdapters;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Signals;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
+{
+    /// <summary>
+    /// Session 683f1eff — a Shell-Core 62407 failure (<c>WhiteGlove_Failed</c>) arrived four
+    /// seconds into the provisioning tracker's 30-s settle window and terminalised the session
+    /// with nothing but its failure type: the HRESULT (0x80070652) and the failed subcategory
+    /// (Apps) the registry had already named never reached the terminal event, the backend
+    /// FailureReason or the termination-time app classification. The coordinator now inherits
+    /// the pending settle detail onto the Shell-Core args and records the terminal-failure
+    /// snapshot from it.
+    /// </summary>
+    public sealed class EspAndHelloTrackerShellCoreFailureInheritanceTests
+    {
+        private static readonly DateTime Fixed = new DateTime(2026, 9, 8, 18, 11, 6, DateTimeKind.Utc);
+
+        private sealed class Fixture : IDisposable
+        {
+            public TempDirectory Tmp { get; } = new TempDirectory();
+            public AgentLogger Logger { get; }
+            public FakeSignalIngressSink Ingress { get; } = new FakeSignalIngressSink();
+            public FakeSignalIngressSink TrackerPostSink { get; } = new FakeSignalIngressSink();
+            public VirtualClock Clock { get; } = new VirtualClock(Fixed);
+            public List<EspFailureDetectedEventArgs> Forwarded { get; } = new List<EspFailureDetectedEventArgs>();
+
+            public Fixture() { Logger = new AgentLogger(Tmp.Path, AgentLogLevel.Debug); }
+
+            public EspAndHelloTracker BuildCoordinator(Func<EspFailureDetectedEventArgs?> pendingProbe)
+            {
+                var coordinator = new EspAndHelloTracker(
+                    sessionId: "S1",
+                    tenantId: "T1",
+                    post: new InformationalEventPost(TrackerPostSink, Clock),
+                    logger: Logger,
+                    skipConfigProbe: () => ((bool?)false, (bool?)false),
+                    accountSetupActivityProbe: () => false,
+                    pendingEspFailureProbe: pendingProbe);
+                coordinator.EspFailureDetected += (_, args) => Forwarded.Add(args);
+                return coordinator;
+            }
+
+            public FakeSignalIngressSink.PostedSignal TerminalSignal() =>
+                Assert.Single(Ingress.Posted, p => p.Kind == DecisionSignalKind.EspTerminalFailure);
+
+            public void Dispose() { Tmp.Dispose(); }
+        }
+
+        private static EspFailureDetectedEventArgs PendingAppsFailure() => new EspFailureDetectedEventArgs(
+            failureType: "Provisioning_DeviceSetup_Apps_Failed",
+            errorCode: "0x80070652",
+            failedSubcategory: "Apps",
+            category: "DeviceSetup",
+            likelyCulpritApps: new[] { "ESP Finalizer US" });
+
+        [Fact]
+        public void ShellCore_failure_inside_the_settle_window_inherits_the_registry_detail()
+        {
+            using var f = new Fixture();
+            using var coordinator = f.BuildCoordinator(PendingAppsFailure);
+            using var adapter = new EspAndHelloTrackerAdapter(coordinator, f.Ingress, f.Clock);
+
+            coordinator.TriggerShellCoreEspFailureForTest("WhiteGlove_Failed");
+
+            var args = Assert.Single(f.Forwarded);
+            Assert.Equal("WhiteGlove_Failed", args.FailureType);   // the signal that terminalised
+            Assert.Equal("0x80070652", args.ErrorCode);
+            Assert.Equal("Apps", args.FailedSubcategory);
+            Assert.Equal("DeviceSetup", args.Category);
+            Assert.Equal(new[] { "ESP Finalizer US" }, args.LikelyCulpritApps);
+
+            // Wire-through: the EspTerminalFailure signal payload carries the detail the
+            // DecisionEngine copies onto enrollment_failed.
+            var signal = f.TerminalSignal();
+            Assert.Equal("WhiteGlove_Failed", signal.Payload!["failureType"]);
+            Assert.Equal("0x80070652", signal.Payload["errorCode"]);
+            Assert.Equal("Apps", signal.Payload["failedSubcategory"]);
+            Assert.Equal("DeviceSetup", signal.Payload["category"]);
+            Assert.Equal("ESP Finalizer US", signal.Payload["likelyCulpritApps"]);
+
+            // Termination-time classification reads the same context.
+            Assert.NotNull(coordinator.LastEspTerminalFailure);
+            Assert.Equal("0x80070652", coordinator.LastEspTerminalFailure.ErrorCode);
+            Assert.True(coordinator.LastEspTerminalFailure.IsAppsSubcategory);
+        }
+
+        [Fact]
+        public void ShellCore_failure_without_a_pending_window_stays_bare()
+        {
+            using var f = new Fixture();
+            using var coordinator = f.BuildCoordinator(() => null);
+            using var adapter = new EspAndHelloTrackerAdapter(coordinator, f.Ingress, f.Clock);
+
+            coordinator.TriggerShellCoreEspFailureForTest("ESPProgress_Timeout");
+
+            var args = Assert.Single(f.Forwarded);
+            Assert.Equal("ESPProgress_Timeout", args.FailureType);
+            Assert.Null(args.ErrorCode);
+            Assert.Null(args.FailedSubcategory);
+            Assert.Null(args.Category);
+            Assert.Empty(args.LikelyCulpritApps);
+            Assert.Null(coordinator.LastEspTerminalFailure);
+
+            var signal = f.TerminalSignal();
+            Assert.False(signal.Payload!.ContainsKey("errorCode"));
+            Assert.False(signal.Payload.ContainsKey("failedSubcategory"));
+        }
+
+        [Fact]
+        public void A_throwing_probe_degrades_to_the_bare_failure()
+        {
+            using var f = new Fixture();
+            using var coordinator = f.BuildCoordinator(() => throw new InvalidOperationException("probe"));
+
+            coordinator.TriggerShellCoreEspFailureForTest("WhiteGlove_Failed");
+
+            var args = Assert.Single(f.Forwarded);
+            Assert.Equal("WhiteGlove_Failed", args.FailureType);
+            Assert.Null(args.ErrorCode);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/EspAndHelloTrackerStarvedAppsTests.cs

@@ -174,7 +174,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
         [Fact]
         public void Reevaluate_does_not_re_emit_starved_warnings()
         {
-            // sits-d Cloud-PC fix (2026-08-19): the synthesis re-check now runs on EVERY IME
+            // Cloud-PC fix (2026-08-19): the synthesis re-check now runs on EVERY IME
             // app-state transition. It must not turn the one-shot starvation warning into a
             // per-transition stream — the re-check path suppresses the emission entirely
             // (the per-appId dedupe would swallow the duplicates, but walking the probe
@@ -198,7 +198,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
         [Fact]
         public void Starved_apps_that_settle_later_still_complete_the_enrollment()
         {
-            // The real sits-d shape: the ESP exits with apps still starved (warning emitted),
+            // The real field shape: the ESP exits with apps still starved (warning emitted),
             // the apps then all settle, and the re-check must open the gate — the warning
             // already on the timeline is history, not a permanent veto.
             using var f = new Fixture();

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/EspAndHelloTrackerUserAppsSettledSynthesisTests.cs

@@ -172,8 +172,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
         }
 
         // ------------------------------------------------------------------------------
-        // sits-d Cloud-PC fix (2026-08-19) — the synthesis is no longer edge-only.
-        // Sessions 8110e262 / a89aac2d: the ESP page exited while 138 required user-ESP apps
+        // Cloud-PC fix (2026-08-19) — the synthesis is no longer edge-only.
+        // Two field sessions: the ESP page exited while 138 required user-ESP apps
         // were still in flight, they all reached a terminal state (0 failed) minutes later,
         // and because nothing re-checked, the enrollment never completed.
         // ------------------------------------------------------------------------------

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/DiagnosticsPathGuardsTests.cs

@@ -0,0 +1,193 @@
+using System;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
+{
+    /// <summary>
+    /// A configured diagnostics entry is resolved to the folder and pattern that get
+    /// enumerated, and the guard judges exactly that folder. The cases below pin the
+    /// property that matters: no spelling of an allowed entry ever selects its parent.
+    /// </summary>
+    public sealed class DiagnosticsPathGuardsTests
+    {
+        private const string TestProfile = @"C:\Users\TestUser";
+
+        private static readonly Func<string, bool> IsDirectory = _ => true;
+        private static readonly Func<string, bool> IsNotDirectory = _ => false;
+
+        private static DiagnosticsPathGuards.CollectionTarget Resolve(
+            string path,
+            bool includeSubfolders = false,
+            bool unrestrictedMode = false,
+            string? userProfilePath = null,
+            Func<string, bool>? directoryExists = null)
+        {
+            Assert.True(DiagnosticsPathGuards.TryResolveCollectionTarget(
+                path, includeSubfolders, unrestrictedMode, userProfilePath!, directoryExists ?? IsDirectory, out var target));
+            return target;
+        }
+
+        private static void AssertRefused(
+            string path,
+            bool unrestrictedMode = false,
+            string? userProfilePath = null,
+            Func<string, bool>? directoryExists = null)
+        {
+            Assert.False(DiagnosticsPathGuards.TryResolveCollectionTarget(
+                path, true, unrestrictedMode, userProfilePath!, directoryExists ?? IsDirectory, out var target));
+            Assert.Null(target);
+        }
+
+        // ------------------------------------------------------------ folder entries
+
+        [Theory]
+        [InlineData(@"C:\Windows\Logs")]
+        [InlineData(@"C:\Windows\Logs\")]
+        [InlineData(@"C:\Windows\SetupDiag")]
+        [InlineData(@"C:\ProgramData\AutopilotMonitor")]
+        [InlineData(@"C:\ProgramData\Microsoft\DiagnosticLogCSP")]
+        public void Folder_entry_collects_from_itself_never_from_its_parent(string configured)
+        {
+            var target = Resolve(configured, includeSubfolders: true);
+
+            Assert.Equal(configured.TrimEnd('\\'), target.Folder, ignoreCase: true);
+            Assert.Equal("*", target.Pattern);
+            Assert.True(target.Recurse);
+        }
+
+        [Fact]
+        public void Trailing_separator_means_folder_even_when_the_folder_does_not_exist_yet()
+        {
+            var target = Resolve(@"C:\Windows\Logs\NotThereYet\", directoryExists: IsNotDirectory);
+
+            Assert.Equal(@"C:\Windows\Logs\NotThereYet", target.Folder, ignoreCase: true);
+            Assert.Equal("*", target.Pattern);
+        }
+
+        [Fact]
+        public void Folder_name_with_a_dot_is_still_a_folder()
+        {
+            var target = Resolve(@"C:\Windows\Logs\vendor.v2");
+
+            Assert.Equal(@"C:\Windows\Logs\vendor.v2", target.Folder, ignoreCase: true);
+            Assert.Equal("*", target.Pattern);
+        }
+
+        // ------------------------------------------------------------ wildcard entries
+
+        [Fact]
+        public void Wildcard_entry_collects_the_pattern_from_its_validated_parent()
+        {
+            var target = Resolve(@"C:\Windows\Panther\*.log", includeSubfolders: true);
+
+            Assert.Equal(@"C:\Windows\Panther", target.Folder, ignoreCase: true);
+            Assert.Equal("*.log", target.Pattern);
+            Assert.True(target.Recurse);
+        }
+
+        [Fact]
+        public void Wildcard_beside_an_allowlisted_file_is_refused()
+        {
+            // Only ReportingEvents.log is on the allowlist, not the folder it lives in.
+            AssertRefused(@"C:\Windows\SoftwareDistribution\*.log");
+        }
+
+        // ------------------------------------------------------------ file entries
+
+        [Fact]
+        public void File_entry_never_recurses_because_its_folder_was_not_validated()
+        {
+            var target = Resolve(
+                @"C:\Windows\SoftwareDistribution\ReportingEvents.log",
+                includeSubfolders: true,
+                directoryExists: IsNotDirectory);
+
+            Assert.Equal(@"C:\Windows\SoftwareDistribution", target.Folder, ignoreCase: true);
+            Assert.Equal("ReportingEvents.log", target.Pattern);
+            Assert.False(target.Recurse);
+        }
+
+        [Fact]
+        public void Missing_path_without_a_dot_is_one_file_name_not_a_wildcard_on_the_parent()
+        {
+            var target = Resolve(@"C:\Windows\Logs\nodot", includeSubfolders: true, directoryExists: IsNotDirectory);
+
+            Assert.Equal(@"C:\Windows\Logs", target.Folder, ignoreCase: true);
+            Assert.Equal("nodot", target.Pattern);
+            Assert.False(target.Recurse);
+        }
+
+        // ------------------------------------------------------------ refusals
+
+        [Theory]
+        [InlineData(@"C:\Windows")]
+        [InlineData(@"C:\ProgramData")]
+        [InlineData(@"C:\ProgramData\Microsoft")]
+        [InlineData(@"C:\Windows\Logs\..\System32")]
+        [InlineData(@"C:\Windows\LogsEvil")]
+        [InlineData("")]
+        public void Paths_outside_the_allowlist_are_refused(string configured)
+        {
+            AssertRefused(configured);
+        }
+
+        [Theory]
+        [InlineData(@"C:\Users")]
+        [InlineData(@"C:\Users\TestUser\Documents")]
+        [InlineData(@"C:\Windows\System32\config")]
+        [InlineData(@"C:\Windows\System32\config\*")]
+        public void Hard_blocks_hold_in_unrestricted_mode(string configured)
+        {
+            AssertRefused(configured, unrestrictedMode: true);
+        }
+
+        // ------------------------------------------------------------ user-profile token
+
+        [Fact]
+        public void Expanded_token_path_outside_AppData_is_refused_even_in_unrestricted_mode()
+        {
+            // The service expands %LOGGED_ON_USER_PROFILE% before the guard sees the path; an
+            // unexpanded token is not under C:\Users lexically and used to slip past the block.
+            AssertRefused(TestProfile + @"\Documents", unrestrictedMode: true, userProfilePath: TestProfile);
+            AssertRefused(TestProfile + @"\Documents\*.txt", unrestrictedMode: true, userProfilePath: TestProfile);
+        }
+
+        [Fact]
+        public void Expanded_token_path_on_the_profile_allowlist_is_admitted_in_restricted_mode()
+        {
+            var target = Resolve(
+                TestProfile + @"\AppData\Local\RealmJoin\Logs\*.log",
+                userProfilePath: TestProfile);
+
+            Assert.Equal(TestProfile + @"\AppData\Local\RealmJoin\Logs", target.Folder, ignoreCase: true);
+            Assert.Equal("*.log", target.Pattern);
+        }
+
+        [Fact]
+        public void Profile_path_without_the_token_stays_blocked()
+        {
+            AssertRefused(TestProfile + @"\AppData\Local\RealmJoin\Logs\*.log", userProfilePath: null);
+        }
+
+        // ------------------------------------------------------------ recursion guard
+
+        [Theory]
+        [InlineData(@"C:\Users")]
+        [InlineData(@"C:\Users\TestUser")]
+        [InlineData(@"C:\Windows\System32\config")]
+        [InlineData(@"C:\Windows\System32\config\RegBack")]
+        public void Recursion_never_enters_a_hard_blocked_subtree_in_unrestricted_mode(string directory)
+        {
+            Assert.False(DiagnosticsPathGuards.IsDirectoryEnterable(directory, unrestrictedMode: true, userProfilePath: null));
+        }
+
+        [Fact]
+        public void Recursion_enters_ordinary_subfolders()
+        {
+            Assert.True(DiagnosticsPathGuards.IsDirectoryEnterable(@"C:\Windows\System32\drivers", unrestrictedMode: true, userProfilePath: null));
+            Assert.True(DiagnosticsPathGuards.IsDirectoryEnterable(@"C:\Windows\Logs\CBS", unrestrictedMode: false, userProfilePath: null));
+            Assert.False(DiagnosticsPathGuards.IsDirectoryEnterable(@"C:\Windows\System32\drivers", unrestrictedMode: false, userProfilePath: null));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/GatherRuleCollectorGuardTests.cs

@@ -41,15 +41,18 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
         }
 
         private GatherRuleContext Context(bool unrestricted = false, string? imeLogPathOverride = null)
-            => new GatherRuleContext(
-                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+        {
+            var logger = new AgentLogger(_tmp.Path, AgentLogLevel.Info);
+            return new GatherRuleContext(
+                logger,
                 "sess", "tenant",
                 evt => _events.Add(evt),
                 imeLogPathOverride,
-                new LogFilePositionTracker())
+                new GatherRuleSessionState("sess", null, logger))
             {
                 UnrestrictedMode = unrestricted
             };
+        }
 
         private static GatherRule Rule(string collectorType, string target,
             Dictionary<string, string>? parameters = null) => new GatherRule
@@ -456,5 +459,124 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
 
             SingleSecurityWarning();
         }
+
+        // -------------------------------------------------------------------
+        // %LOGGED_ON_USER_PROFILE% exception (userProfilePath overload)
+        //
+        // The token lifts the C:\Users hard block for AppData\Local and
+        // AppData\Roaming — and nothing more. The allowlist still decides,
+        // which is what the cases below pin down: the exception is a gate the
+        // allowlist has to open, never an allowance of its own.
+        // -------------------------------------------------------------------
+
+        private const string TestProfile = @"C:\Users\TestUser";
+
+        [Fact]
+        public void UserProfile_AppDataPath_WithoutAllowlistEntry_IsStillBlocked()
+        {
+            // The lifted hard block alone admits nothing: without a matching
+            // userProfileFilePrefixes entry the path falls through to the
+            // allowlist and is refused there.
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                TestProfile + @"\AppData\Local\UnlistedVendor\app.log",
+                unrestrictedMode: false, userProfilePath: TestProfile));
+        }
+
+        [Fact]
+        public void UserProfile_OutsideAppData_IsBlockedByTheHardBlock()
+        {
+            foreach (var target in new[] { @"\Desktop\secret.txt", @"\Documents\notes.txt", @"\ntuser.dat" })
+            {
+                Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                    TestProfile + target, unrestrictedMode: false, userProfilePath: TestProfile));
+            }
+        }
+
+        [Fact]
+        public void UserProfile_NullProfile_KeepsTheUsersHardBlock()
+        {
+            // No interactive user detected — the exception cannot apply and the
+            // path stays under the plain C:\Users block.
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                @"C:\Users\TestUser\AppData\Local\UnlistedVendor\app.log",
+                unrestrictedMode: false, userProfilePath: null));
+        }
+
+        [Fact]
+        public void UserProfile_TraversalOutOfAppData_IsBlocked()
+        {
+            // Spelling Documents as a traversal out of AppData must not survive
+            // Path.GetFullPath normalisation.
+            const string traversal = @"C:\Users\TestUser\AppData\Local\..\..\Documents\secret.txt";
+
+            Assert.Equal(@"C:\Users\TestUser\Documents\secret.txt", Path.GetFullPath(traversal));
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                traversal, unrestrictedMode: false, userProfilePath: TestProfile));
+        }
+
+        [Fact]
+        public void UserProfile_ForeignProfile_IsBlockedEvenUnderAppData()
+        {
+            // The exception is scoped to the DETECTED profile — a rule must not
+            // reach a second user's AppData by spelling the path out.
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                @"C:\Users\OtherUser\AppData\Local\UnlistedVendor\app.log",
+                unrestrictedMode: false, userProfilePath: TestProfile));
+        }
+
+        [Fact]
+        public void UserProfile_AllowlistedVendorFolder_IsAllowed()
+        {
+            // AppData\Local\RealmJoin is on userProfileFilePrefixes: the file itself, a
+            // subfolder below it, and the folder itself all pass.
+            foreach (var target in new[] { @"\tray.log", @"\Logs\rj.log", "" })
+            {
+                Assert.True(GatherRuleGuards.IsFilePathAllowed(
+                    TestProfile + @"\AppData\Local\RealmJoin" + target,
+                    unrestrictedMode: false, userProfilePath: TestProfile),
+                    $"expected allowed: ...\\RealmJoin{target}");
+            }
+        }
+
+        [Fact]
+        public void UserProfile_SiblingOfAnAllowlistedVendorFolder_IsBlocked()
+        {
+            // Segment-bounded: "RealmJoin" must not admit "RealmJoinSomethingElse".
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                TestProfile + @"\AppData\Local\RealmJoinSomethingElse\tray.log",
+                unrestrictedMode: false, userProfilePath: TestProfile));
+        }
+
+        [Fact]
+        public void UserProfile_AllowlistedVendorFolder_InAForeignProfile_IsBlocked()
+        {
+            // The allowlist is anchored to the DETECTED profile, not to C:\Users\*.
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                @"C:\Users\OtherUser\AppData\Local\RealmJoin\tray.log",
+                unrestrictedMode: false, userProfilePath: TestProfile));
+        }
+
+        [Fact]
+        public void UserProfile_AllowlistedVendorFolder_WithoutADetectedUser_IsBlocked()
+        {
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                @"C:\Users\TestUser\AppData\Local\RealmJoin\tray.log",
+                unrestrictedMode: false, userProfilePath: null));
+        }
+
+        [Fact]
+        public void UserProfile_AppDataPath_IsAllowedInUnrestrictedMode()
+        {
+            // Where the exception does bite today: unrestricted mode returns
+            // before the allowlist, so the lifted hard block is the whole story.
+            Assert.True(GatherRuleGuards.IsFilePathAllowed(
+                TestProfile + @"\AppData\Local\UnlistedVendor\app.log",
+                unrestrictedMode: true, userProfilePath: TestProfile));
+
+            // ...but only under AppData — Documents stays blocked even there.
+            Assert.False(GatherRuleGuards.IsFilePathAllowed(
+                TestProfile + @"\Documents\secret.txt",
+                unrestrictedMode: true, userProfilePath: TestProfile));
+        }
     }
 }

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/GatherRuleDebugLogTests.cs

@@ -94,7 +94,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
         public void Context_DebugLog_is_noop_without_writer()
         {
             var context = new GatherRuleContext(
-                _logger, "sess", "tenant", _ => { }, null, new LogFilePositionTracker());
+                _logger, "sess", "tenant", _ => { }, null, new GatherRuleSessionState("sess", null, _logger));
 
             context.DebugLog("RULE-1", GatherRuleDebugLog.StageScope, "should not throw, should not write");
 

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/GatherRuleExecutorEnrichErrorCodesTests.cs

@@ -0,0 +1,111 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Threading;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
+{
+    /// <summary>
+    /// <see cref="GatherRule.EnrichErrorCodes"/> is an opt-in the backend honours at response time:
+    /// the agent stamps <c>enrichErrorCodes: true</c> into the event data of a rule that set it and
+    /// nothing at all otherwise (the default payload stays as it was).
+    /// </summary>
+    [Collection("SerialThreading")] // startup rules execute on the shared ThreadPool
+    public sealed class GatherRuleExecutorEnrichErrorCodesTests : IDisposable
+    {
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly List<EnrollmentEvent> _events = new List<EnrollmentEvent>();
+        private readonly object _eventsGate = new object();
+        private readonly GatherRuleExecutor _executor;
+
+        private const string AbsentPath =
+            "HKLM\\SOFTWARE\\AutopilotMonitorTests\\DefinitelyAbsent_7e3a1f4b-0000-0000-0000-000000000000";
+
+        public GatherRuleExecutorEnrichErrorCodesTests()
+        {
+            var logger = new AgentLogger(_tmp.Path, AgentLogLevel.Info);
+            _executor = new GatherRuleExecutor(
+                "sess", "tenant",
+                evt => { lock (_eventsGate) _events.Add(evt); },
+                logger)
+            {
+                UnrestrictedMode = true
+            };
+        }
+
+        public void Dispose()
+        {
+            _executor.Dispose();
+            _tmp.Dispose();
+        }
+
+        private EnrollmentEvent SingleEvent()
+        {
+            lock (_eventsGate) return Assert.Single(_events);
+        }
+
+        private bool WaitForEventCount(int count, int timeoutMs = 10000)
+        {
+            var sw = Stopwatch.StartNew();
+            while (sw.ElapsedMilliseconds < timeoutMs)
+            {
+                lock (_eventsGate) if (_events.Count >= count) return true;
+                Thread.Sleep(25);
+            }
+            lock (_eventsGate) return _events.Count >= count;
+        }
+
+        private static GatherRule StartupRule(bool enrichErrorCodes) => new GatherRule
+        {
+            RuleId = "GATHER-EEC-001",
+            Title = "enrich test",
+            CollectorType = "registry",
+            Target = AbsentPath,
+            Trigger = "startup",
+            OutputEventType = "gather_test",
+            Enabled = true,
+            EnrichErrorCodes = enrichErrorCodes,
+        };
+
+        [Fact]
+        public void StampRuleMarkers_AddsMarkerOnlyWhenOptedIn()
+        {
+            var optedIn = new Dictionary<string, object> { ["exitCode"] = "1603" };
+            GatherRuleExecutor.StampRuleMarkers(StartupRule(enrichErrorCodes: true), optedIn);
+            Assert.Equal(true, optedIn[Constants.GatherRuleDataKeys.EnrichErrorCodes]);
+
+            var defaultRule = new Dictionary<string, object> { ["exitCode"] = "1603" };
+            GatherRuleExecutor.StampRuleMarkers(StartupRule(enrichErrorCodes: false), defaultRule);
+            Assert.False(defaultRule.ContainsKey(Constants.GatherRuleDataKeys.EnrichErrorCodes));
+            Assert.Single(defaultRule);
+        }
+
+        [Fact]
+        public void ExecuteRule_StampsMarker_WhenRuleOptsIn()
+        {
+            _executor.UpdateRules(new List<GatherRule> { StartupRule(enrichErrorCodes: true) });
+
+            Assert.True(_executor.WaitForStartupRules(30));
+            Assert.True(WaitForEventCount(1));
+            var evt = SingleEvent();
+            Assert.Equal(GatherRuleExecutor.SourceName, evt.Source);
+            Assert.Equal(true, evt.Data[Constants.GatherRuleDataKeys.EnrichErrorCodes]);
+        }
+
+        [Fact]
+        public void ExecuteRule_LeavesPayloadUnchanged_ByDefault()
+        {
+            _executor.UpdateRules(new List<GatherRule> { StartupRule(enrichErrorCodes: false) });
+
+            Assert.True(_executor.WaitForStartupRules(30));
+            Assert.True(WaitForEventCount(1));
+            Assert.False(SingleEvent().Data.ContainsKey(Constants.GatherRuleDataKeys.EnrichErrorCodes));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/GatherRuleExecutorRestartTests.cs

@@ -0,0 +1,220 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Newtonsoft.Json;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
+{
+    /// <summary>
+    /// An agent restart inside one enrollment session — a new <see cref="GatherRuleExecutor"/> on the
+    /// same state directory — continues where the previous run stopped: logparser rules do not
+    /// replay their log, on_change rules do not re-emit an unchanged result. Regression anchor:
+    /// session c8106021, where every restart replayed the whole HP Image Assistant log (70 events).
+    /// </summary>
+    [Collection("SerialThreading")] // startup rules execute on the shared ThreadPool
+    public sealed class GatherRuleExecutorRestartTests : IDisposable
+    {
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly TempDirectory _stateDir = new TempDirectory();
+        private readonly List<EnrollmentEvent> _events = new List<EnrollmentEvent>();
+        private readonly object _eventsGate = new object();
+        private readonly List<GatherRuleExecutor> _executors = new List<GatherRuleExecutor>();
+
+        // %TEMP% lives under C:\Users (hard-blocked) — log targets sit beside the test assembly.
+        private readonly string _logDir = Path.Combine(
+            AppContext.BaseDirectory, "gather-restart-tests-" + Guid.NewGuid().ToString("N"));
+
+        public GatherRuleExecutorRestartTests()
+        {
+            Directory.CreateDirectory(_logDir);
+        }
+
+        public void Dispose()
+        {
+            foreach (var executor in _executors)
+                executor.Dispose();
+            _tmp.Dispose();
+            _stateDir.Dispose();
+            try { Directory.Delete(_logDir, recursive: true); } catch { /* best effort */ }
+        }
+
+        private string StateFile => Path.Combine(_stateDir.Path, GatherRuleStatePersistence.FileName);
+
+        private List<EnrollmentEvent> Events
+        {
+            get { lock (_eventsGate) return _events.ToList(); }
+        }
+
+        /// <summary>One agent run: a fresh executor whose startup rules run once. Not disposed — a hard kill.</summary>
+        private GatherRuleExecutor AgentRun(GatherRule rule, string sessionId = "session-a", string? stateDirectory = "default",
+            Action<EnrollmentEvent>? onEvent = null, string? debugLogPath = null)
+        {
+            var executor = new GatherRuleExecutor(
+                sessionId, "tenant",
+                evt =>
+                {
+                    onEvent?.Invoke(evt);
+                    lock (_eventsGate) _events.Add(evt);
+                },
+                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                debugLogPath: debugLogPath,
+                stateDirectory: stateDirectory == "default" ? _stateDir.Path : stateDirectory)
+            {
+                UnrestrictedMode = true
+            };
+            _executors.Add(executor);
+            executor.UpdateRules(new List<GatherRule> { rule });
+            Assert.True(executor.WaitForStartupRules(30));
+            return executor;
+        }
+
+        private static GatherRule LogRule(string path, string id = "hpia-log-collect") => new GatherRule
+        {
+            RuleId = id,
+            Title = id,
+            CollectorType = "logparser",
+            Target = path,
+            Parameters = new Dictionary<string, string> { ["pattern"] = "^(?<status>Update .+)$", ["format"] = "text" },
+            Trigger = "startup",
+            OutputEventType = "HPiA-UpdateStatus",
+            Enabled = true,
+        };
+
+        private static GatherRule OnChangeFileRule(string path) => new GatherRule
+        {
+            RuleId = "GATHER-OC-FILE",
+            Title = "file presence",
+            CollectorType = "file",
+            Target = path,
+            Trigger = "startup",
+            OutputEventType = "gather_file_presence",
+            Enabled = true,
+            EmitMode = "on_change",
+        };
+
+        private string WriteLog(string name, string content)
+        {
+            var path = Path.Combine(_logDir, name);
+            File.WriteAllText(path, content);
+            return path;
+        }
+
+        private int StatusEvents => Events.Count(e => e.EventType == "HPiA-UpdateStatus");
+
+        [Fact]
+        public void Restart_does_not_replay_the_log_and_new_lines_arrive_once()
+        {
+            var path = WriteLog("HP Image Assistant.log", "Update one\nUpdate two\nnoise\n");
+
+            AgentRun(LogRule(path));
+            Assert.Equal(2, StatusEvents);
+
+            AgentRun(LogRule(path));                      // reboot, nothing new
+            Assert.Equal(2, StatusEvents);
+
+            File.AppendAllText(path, "Update three\n");
+            AgentRun(LogRule(path));                      // next restart picks up only the new line
+            Assert.Equal(3, StatusEvents);
+            Assert.Equal("Update three", Events.Last(e => e.EventType == "HPiA-UpdateStatus").Data["status"]);
+        }
+
+        [Fact]
+        public void Position_is_on_disk_right_after_the_run_without_a_clean_shutdown()
+        {
+            var path = WriteLog("hardkill.log", "Update one\n");
+
+            AgentRun(LogRule(path));                      // never disposed
+
+            var saved = JsonConvert.DeserializeObject<GatherRuleStateData>(File.ReadAllText(StateFile))!;
+            var position = Assert.Single(saved.LogPositions!);
+            Assert.Equal(new FileInfo(path).Length, position.Position);
+            Assert.Equal("session-a", saved.SessionId);
+        }
+
+        [Fact]
+        public void Position_is_saved_only_after_the_events_went_out()
+        {
+            var path = WriteLog("ordering.log", "Update one\n");
+            var savedDuringEmit = new List<bool>();
+
+            AgentRun(LogRule(path), onEvent: _ => savedDuringEmit.Add(File.Exists(StateFile)));
+
+            Assert.Equal(new[] { false }, savedDuringEmit);
+            Assert.True(File.Exists(StateFile));
+        }
+
+        [Fact]
+        public void A_new_session_reads_the_log_from_the_beginning()
+        {
+            var path = WriteLog("rotated.log", "Update one\nUpdate two\n");
+            AgentRun(LogRule(path), sessionId: "session-a");
+
+            AgentRun(LogRule(path), sessionId: "session-b");   // session rotated on the same device
+
+            Assert.Equal(4, StatusEvents);
+        }
+
+        [Fact]
+        public void A_log_replaced_during_the_reboot_is_read_from_the_beginning()
+        {
+            var path = WriteLog("replaced.log", "Update one\n");
+            AgentRun(LogRule(path, "replaced"));
+
+            // The tool writes a new log after the reboot; it is already longer than the old position.
+            File.WriteAllText(path, "Update fresh A\nUpdate fresh B\nUpdate fresh C\n");
+            AgentRun(LogRule(path, "replaced"));
+
+            Assert.Equal(new[] { "Update one", "Update fresh A", "Update fresh B", "Update fresh C" },
+                Events.Where(e => e.EventType == "HPiA-UpdateStatus").Select(e => (string)e.Data["status"]).ToArray());
+        }
+
+        [Fact]
+        public void An_unchanged_on_change_result_stays_silent_after_a_restart()
+        {
+            var watched = Path.Combine(_logDir, "marker.txt");
+
+            AgentRun(OnChangeFileRule(watched));          // absent → first result emits
+            AgentRun(OnChangeFileRule(watched));          // reboot, still absent → silent
+            Assert.Single(Events, e => e.EventType == "gather_file_presence");
+
+            File.WriteAllText(watched, "present");
+            AgentRun(OnChangeFileRule(watched));          // changed → emits
+
+            Assert.Equal(2, Events.Count(e => e.EventType == "gather_file_presence"));
+        }
+
+        [Fact]
+        public void Without_a_state_directory_every_run_starts_over_and_writes_nothing()
+        {
+            var path = WriteLog("diagnostic.log", "Update one\n");
+
+            AgentRun(LogRule(path), stateDirectory: null);
+            AgentRun(LogRule(path), stateDirectory: null);
+
+            Assert.Equal(2, StatusEvents);
+            Assert.False(File.Exists(StateFile));
+        }
+
+        [Fact]
+        public void Debug_trace_says_what_was_restored_and_where_reading_continues()
+        {
+            var path = WriteLog("traced.log", "Update one\n");
+            var trace = Path.Combine(_tmp.Path, "gather-rules-debug.log");
+            AgentRun(LogRule(path));
+            File.AppendAllText(path, "Update two\n");
+
+            AgentRun(LogRule(path), debugLogPath: trace);
+
+            var text = File.ReadAllText(trace);
+            Assert.Contains("gather state: restored 1 logparser position(s) for 1 rule(s)", text);
+            Assert.Contains("hpia-log-collect | config | logparser position restored: traced.log", text);
+            Assert.Contains("traced.log: continuing at position", text);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/GatherRuleSessionStateTests.cs

@@ -0,0 +1,278 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather.Collectors;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using Newtonsoft.Json;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
+{
+    /// <summary>
+    /// <see cref="GatherRuleSessionState"/> and <see cref="GatherRuleStatePersistence"/>: what is
+    /// written, what a restart restores, what it refuses, and when the file is (not) written.
+    /// </summary>
+    public sealed class GatherRuleSessionStateTests : IDisposable
+    {
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly TempDirectory _stateDir = new TempDirectory();
+        private readonly AgentLogger _logger;
+
+        public GatherRuleSessionStateTests()
+        {
+            _logger = new AgentLogger(_tmp.Path, AgentLogLevel.Info);
+        }
+
+        public void Dispose()
+        {
+            _tmp.Dispose();
+            _stateDir.Dispose();
+        }
+
+        private string StateFile => Path.Combine(_stateDir.Path, GatherRuleStatePersistence.FileName);
+
+        private GatherRuleSessionState NewState(string sessionId = "session-a") =>
+            new GatherRuleSessionState(sessionId, new GatherRuleStatePersistence(_stateDir.Path, _logger), _logger);
+
+        private static LogFileHead Head(string text) => LogFileHead.FromBytes(Encoding.UTF8.GetBytes(text));
+
+        // ── restore ─────────────────────────────────────────────────────────
+
+        [Fact]
+        public void Positions_and_emitted_hashes_survive_a_restart_of_the_same_session()
+        {
+            var first = NewState();
+            first.CommitLogPosition("RULE-1", @"C:\Logs\a.log", 120, 7, Head("2026-09-28 a.log start"), heldTailStart: -1);
+            first.CommitEmittedHash("RULE-2", "hash-value");
+
+            var second = NewState();
+
+            var position = second.PeekLogPosition("RULE-1", @"C:\Logs\a.log");
+            Assert.NotNull(position);
+            Assert.Equal(120, position!.Position);
+            Assert.Equal(7, position.LineNumber);
+            Assert.True(position.FromPreviousRun);
+            Assert.Equal("hash-value", second.GetEmittedHashes()["RULE-2"]);
+            Assert.StartsWith("restored 1 logparser position(s) for 1 rule(s) and 1 on_change value(s)", second.RestoreSummary);
+        }
+
+        [Fact]
+        public void State_of_another_session_is_ignored()
+        {
+            NewState("session-a").CommitLogPosition("RULE-1", @"C:\Logs\a.log", 120, 7, Head("start"), -1);
+
+            var rotated = NewState("session-b");
+
+            Assert.Null(rotated.PeekLogPosition("RULE-1", @"C:\Logs\a.log"));
+            Assert.Contains("saved for session session-a, current session is session-b", rotated.RestoreSummary);
+        }
+
+        [Fact]
+        public void Missing_file_is_a_first_run_and_corrupt_file_a_fresh_start()
+        {
+            Assert.StartsWith("no saved state", NewState().RestoreSummary);
+
+            File.WriteAllText(StateFile, "not json {{{");
+            var afterCorruption = NewState();
+
+            Assert.StartsWith("saved state discarded", afterCorruption.RestoreSummary);
+            Assert.Empty(afterCorruption.GetEmittedHashes());
+        }
+
+        [Fact]
+        public void Tampered_entries_are_dropped_and_the_rest_restored()
+        {
+            var data = new GatherRuleStateData
+            {
+                SessionId = "session-a",
+                SavedAtUtc = DateTime.UtcNow,
+                LogPositions = new List<GatherLogPositionData>
+                {
+                    new GatherLogPositionData { RuleId = "OK", Path = @"C:\a.log", Position = 10, LineNumber = 1, HeadLength = 10, HeadHash = "h" },
+                    new GatherLogPositionData { RuleId = "NEG", Path = @"C:\b.log", Position = -5, HeadLength = 10, HeadHash = "h" },
+                    new GatherLogPositionData { RuleId = "", Path = @"C:\c.log", Position = 1, HeadLength = 1, HeadHash = "h" },
+                    new GatherLogPositionData { RuleId = "BIGHEAD", Path = @"C:\d.log", Position = 1, HeadLength = 5000, HeadHash = "h" },
+                    new GatherLogPositionData { RuleId = "NOHEAD", Path = @"C:\e.log", Position = 50, HeadLength = 0 },
+                },
+                OnChangeHashes = new Dictionary<string, string> { ["GOOD"] = "x", ["EMPTY"] = "" },
+            };
+            File.WriteAllText(StateFile, JsonConvert.SerializeObject(data));
+
+            var state = NewState();
+
+            Assert.NotNull(state.PeekLogPosition("OK", @"C:\a.log"));
+            Assert.Null(state.PeekLogPosition("NEG", @"C:\b.log"));
+            Assert.Null(state.PeekLogPosition("BIGHEAD", @"C:\d.log"));
+            Assert.Null(state.PeekLogPosition("NOHEAD", @"C:\e.log"));
+            Assert.Equal(new[] { "GOOD" }, state.GetEmittedHashes().Keys.ToArray());
+            Assert.Contains("5 invalid entries dropped", state.RestoreSummary);
+        }
+
+        [Fact]
+        public void A_path_no_real_file_can_have_is_dropped_and_never_stops_the_executor()
+        {
+            // Path APIs throw on these characters under .NET Framework; a throw here would keep
+            // every collector host down at every restart of the session.
+            var data = new GatherRuleStateData
+            {
+                SessionId = "session-a",
+                LogPositions = new List<GatherLogPositionData>
+                {
+                    new GatherLogPositionData { RuleId = "BAD", Path = "C:\\Logs\\x.|og", Position = 1, HeadLength = 1, HeadHash = "h" },
+                    new GatherLogPositionData { RuleId = "WILD", Path = "C:\\Logs\\*.log", Position = 1, HeadLength = 1, HeadHash = "h" },
+                    new GatherLogPositionData { RuleId = "OK", Path = "C:\\Logs\\ok.log", Position = 1, HeadLength = 1, HeadHash = "h" },
+                },
+            };
+            File.WriteAllText(StateFile, JsonConvert.SerializeObject(data));
+
+            var state = NewState();
+
+            Assert.NotNull(state.PeekLogPosition("OK", "C:\\Logs\\ok.log"));
+            Assert.Null(state.PeekLogPosition("BAD", "C:\\Logs\\x.|og"));
+            Assert.Contains("2 invalid entries dropped", state.RestoreSummary);
+        }
+
+        // ── where reading starts ────────────────────────────────────────────
+
+        [Fact]
+        public void Reading_continues_while_the_file_head_still_matches()
+        {
+            var state = NewState();
+            state.CommitLogPosition("R", @"C:\a.log", 30, 3, Head("2026-09-28 first line\n"), -1);
+
+            var start = GatherRuleSessionState.ResolveStart(state.PeekLogPosition("R", @"C:\a.log"), 200,
+                Head("2026-09-28 first line\nsecond line\nthird"), out var how);
+
+            Assert.Equal(30, start);
+            Assert.Equal(LogReadStart.Continue, how);
+        }
+
+        [Fact]
+        public void A_shrunk_file_and_a_replaced_file_are_read_from_the_beginning()
+        {
+            var state = NewState();
+            state.CommitLogPosition("R", @"C:\a.log", 30, 3, Head("2026-09-28 first line\n"), -1);
+            var known = state.PeekLogPosition("R", @"C:\a.log");
+
+            Assert.Equal(0, GatherRuleSessionState.ResolveStart(known, 20, Head("2026-09-28 fir"), out var shrunk));
+            Assert.Equal(LogReadStart.Shrunk, shrunk);
+
+            // Replaced and already longer than the old position: only the head tells.
+            Assert.Equal(0, GatherRuleSessionState.ResolveStart(known, 500, Head("2026-09-30 a new log entirely, much longer"), out var replaced));
+            Assert.Equal(LogReadStart.Replaced, replaced);
+
+            // Shorter than the recorded head although not shorter than the position.
+            state.CommitLogPosition("S", @"C:\b.log", 5, 1, Head("0123456789abcdef"), -1);
+            Assert.Equal(0, GatherRuleSessionState.ResolveStart(state.PeekLogPosition("S", @"C:\b.log"), 8, Head("01234567"), out var cut));
+            Assert.Equal(LogReadStart.Replaced, cut);
+        }
+
+        [Fact]
+        public void Positions_are_kept_per_rule_for_the_same_file()
+        {
+            var state = NewState();
+            state.CommitLogPosition("RULE-A", @"C:\shared.log", 100, 10, Head("x"), -1);
+
+            Assert.Null(state.PeekLogPosition("RULE-B", @"C:\shared.log"));
+            Assert.NotNull(state.PeekLogPosition("RULE-A", @"C:\SHARED.LOG")); // paths compare case-insensitively
+        }
+
+        // ── when the file is written ────────────────────────────────────────
+
+        [Fact]
+        public void An_unchanged_commit_does_not_write_the_file()
+        {
+            var state = NewState();
+            state.CommitLogPosition("R", @"C:\a.log", 10, 1, Head("head"), -1);
+            File.Delete(StateFile);
+
+            state.CommitLogPosition("R", @"C:\a.log", 10, 1, Head("head"), -1);
+            state.CommitEmittedHash("H", "v");
+            File.Delete(StateFile);
+            state.CommitEmittedHash("H", "v");
+
+            Assert.False(File.Exists(StateFile));
+        }
+
+        [Fact]
+        public void A_failed_save_is_retried_at_the_next_commit()
+        {
+            var blocked = Path.Combine(_stateDir.Path, "blocked");
+            File.WriteAllText(blocked, "a file where the state directory should be");
+            var state = new GatherRuleSessionState("session-a", new GatherRuleStatePersistence(blocked, _logger), _logger);
+
+            state.CommitEmittedHash("H", "v");   // Directory.CreateDirectory fails
+            File.Delete(blocked);
+            state.CommitEmittedHash("H", "v");   // unchanged, but the earlier save is still owed
+
+            Assert.True(File.Exists(Path.Combine(blocked, GatherRuleStatePersistence.FileName)));
+        }
+
+        [Fact]
+        public void A_closed_state_no_longer_writes()
+        {
+            var state = NewState();
+            state.Close();
+
+            state.CommitEmittedHash("H", "v");
+
+            Assert.False(File.Exists(StateFile));
+        }
+
+        [Fact]
+        public void Without_persistence_nothing_is_written()
+        {
+            var state = new GatherRuleSessionState("session-a", null, _logger);
+
+            state.CommitLogPosition("R", @"C:\a.log", 10, 1, Head("head"), -1);
+
+            Assert.StartsWith("persistence off", state.RestoreSummary);
+            Assert.Empty(Directory.GetFiles(_stateDir.Path));
+        }
+
+        // ── bounds and concurrency ──────────────────────────────────────────
+
+        [Fact]
+        public void A_rule_forgets_its_least_recently_touched_file_beyond_the_cap()
+        {
+            var state = NewState();
+            for (var i = 0; i < GatherRuleSessionState.MaxLogFilesPerRule; i++)
+                state.CommitLogPosition("R", $@"C:\logs\{i}.log", 1, 1, Head("h"), -1);
+            state.PeekLogPosition("R", @"C:\logs\0.log");   // touched again — survives
+
+            state.CommitLogPosition("R", @"C:\logs\new.log", 1, 1, Head("h"), -1);
+
+            Assert.NotNull(state.PeekLogPosition("R", @"C:\logs\0.log"));
+            Assert.Null(state.PeekLogPosition("R", @"C:\logs\1.log"));
+            Assert.NotNull(state.PeekLogPosition("R", @"C:\logs\new.log"));
+        }
+
+        [Fact]
+        public void Parallel_commits_leave_a_consistent_file()
+        {
+            var state = NewState();
+
+            Parallel.For(0, 8, worker =>
+            {
+                for (var i = 0; i < 50; i++)
+                {
+                    state.CommitLogPosition($"RULE-{worker}", $@"C:\logs\{worker}.log", i + 1, i, Head("h"), -1);
+                    state.PeekLogPosition($"RULE-{worker}", $@"C:\logs\{worker}.log");
+                    state.CommitEmittedHash($"RULE-{worker}", "hash-" + i);
+                }
+            });
+
+            var restored = NewState();
+            for (var worker = 0; worker < 8; worker++)
+            {
+                Assert.Equal(50, restored.PeekLogPosition($"RULE-{worker}", $@"C:\logs\{worker}.log")!.Position);
+                Assert.Equal("hash-49", restored.GetEmittedHashes()[$"RULE-{worker}"]);
+            }
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/LogLineReaderTests.cs

@@ -0,0 +1,188 @@
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather.Collectors;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
+{
+    /// <summary>
+    /// <see cref="LogLineReader"/>, <see cref="LogTextEncoding"/> and <see cref="LogFileHead"/>:
+    /// exact byte positions, StreamReader-compatible line ends, byte order marks only at offset 0,
+    /// and the code-unit view of UTF-16/UTF-32 files.
+    /// </summary>
+    public sealed class LogLineReaderTests
+    {
+        private static byte[] Bytes(Encoding encoding, string text, bool withBom = true)
+        {
+            var body = encoding.GetBytes(text);
+            return withBom ? encoding.GetPreamble().Concat(body).ToArray() : body;
+        }
+
+        private static (List<string> Lines, List<long> EndPositions, List<bool> Terminated) ReadAll(
+            byte[] file, long start = 0, int maxLineBytes = 1024)
+        {
+            var encoding = LogFileHead.FromBytes(file.Take(LogFileHead.MaxBytes).ToArray()).Encoding;
+            using (var stream = new MemoryStream(file))
+            {
+                stream.Seek(start, SeekOrigin.Begin);
+                var reader = new LogLineReader(stream, encoding, maxLineBytes);
+                var lines = new List<string>();
+                var ends = new List<long>();
+                var terminated = new List<bool>();
+                string line;
+                while ((line = reader.ReadLine()) != null)
+                {
+                    lines.Add(line);
+                    ends.Add(reader.Position);
+                    terminated.Add(reader.LastLineTerminated);
+                }
+                return (lines, ends, terminated);
+            }
+        }
+
+        [Fact]
+        public void Line_ends_match_StreamReader_including_a_lone_carriage_return()
+        {
+            var file = Encoding.UTF8.GetBytes("one\ntwo\r\nthree\rfour");
+
+            var result = ReadAll(file);
+
+            Assert.Equal(new[] { "one", "two", "three", "four" }, result.Lines);
+            Assert.Equal(new long[] { 4, 9, 15, 19 }, result.EndPositions);
+            Assert.Equal(new[] { true, true, true, false }, result.Terminated);
+        }
+
+        [Fact]
+        public void Position_after_each_line_is_the_offset_to_resume_from()
+        {
+            var file = Encoding.UTF8.GetBytes("alpha\nbeta\ngamma\n");
+
+            var first = ReadAll(file);
+            var resumed = ReadAll(file, start: first.EndPositions[0]);
+
+            Assert.Equal(new[] { "beta", "gamma" }, resumed.Lines);
+            Assert.Equal(file.Length, resumed.EndPositions.Last());
+        }
+
+        [Fact]
+        public void Utf8_byte_order_mark_is_skipped_only_at_offset_0()
+        {
+            var file = Bytes(Encoding.UTF8, "first\nsecond\n");
+
+            var result = ReadAll(file);
+
+            Assert.Equal(new[] { "first", "second" }, result.Lines);
+            Assert.Equal(LogTextEncoding.Utf8WithBom, LogFileHead.FromBytes(file).Encoding);
+        }
+
+        [Theory]
+        [InlineData("utf-16le")]
+        [InlineData("utf-16be")]
+        [InlineData("utf-32le")]
+        [InlineData("utf-32be")]
+        public void Unicode_files_are_read_in_their_code_units_from_any_resume_point(string name)
+        {
+            var encoding = name == "utf-16le" ? Encoding.Unicode
+                : name == "utf-16be" ? Encoding.BigEndianUnicode
+                : name == "utf-32le" ? Encoding.UTF32
+                : new UTF32Encoding(bigEndian: true, byteOrderMark: true);
+            var file = Bytes(encoding, "ERROR first\r\nERROR zweite Zeile mit Umlaut äöü\r\n");
+
+            var whole = ReadAll(file);
+            var resumed = ReadAll(file, start: whole.EndPositions[0]);
+
+            Assert.Equal(name, LogFileHead.FromBytes(file).Encoding.Name);
+            Assert.Equal(new[] { "ERROR first", "ERROR zweite Zeile mit Umlaut äöü" }, whole.Lines);
+            Assert.Equal(new[] { "ERROR zweite Zeile mit Umlaut äöü" }, resumed.Lines);
+            Assert.Equal(file.Length, whole.EndPositions.Last());
+        }
+
+        [Fact]
+        public void File_without_byte_order_mark_is_utf8_and_ansi_bytes_decode_as_before()
+        {
+            var file = new byte[] { (byte)'M', (byte)'a', (byte)'n', 0xFC, (byte)'\n' }; // "Man" + Windows-1252 'ü'
+
+            var result = ReadAll(file);
+
+            Assert.Equal(LogTextEncoding.Utf8, LogFileHead.FromBytes(file).Encoding);
+            Assert.Equal(new StreamReader(new MemoryStream(file), Encoding.UTF8).ReadLine(), result.Lines.Single());
+        }
+
+        [Fact]
+        public void Carriage_return_at_end_of_file_ends_the_line_and_its_late_line_feed_is_skipped()
+        {
+            var firstWrite = Encoding.UTF8.GetBytes("done\r");
+            var later = Encoding.UTF8.GetBytes("done\r\nnext\n");
+
+            var first = ReadAll(firstWrite);
+            var resumed = ReadAll(later, start: first.EndPositions.Last());
+
+            Assert.Equal(new[] { "done" }, first.Lines);
+            Assert.True(first.Terminated.Single());
+            Assert.Equal(new[] { "next" }, resumed.Lines);
+        }
+
+        [Fact]
+        public void Overlong_line_is_consumed_without_being_kept_and_reading_continues_behind_it()
+        {
+            var file = Encoding.UTF8.GetBytes(new string('x', 50) + "\nshort\n");
+            using (var stream = new MemoryStream(file))
+            {
+                var reader = new LogLineReader(stream, LogTextEncoding.Utf8, maxLineBytes: 10);
+
+                Assert.Equal(string.Empty, reader.ReadLine());
+                Assert.True(reader.LastLineTruncated);
+                Assert.Equal(51, reader.Position);
+                Assert.Equal("short", reader.ReadLine());
+                Assert.False(reader.LastLineTruncated);
+                Assert.Null(reader.ReadLine());
+            }
+        }
+
+        [Fact]
+        public void Line_spanning_many_read_buffers_is_returned_whole()
+        {
+            var longLine = new string('y', 200_000);
+            var file = Encoding.UTF8.GetBytes(longLine + "\nend\n");
+
+            var result = ReadAll(file, maxLineBytes: 1_000_000);
+
+            Assert.Equal(new[] { longLine, "end" }, result.Lines);
+        }
+
+        [Fact]
+        public void Half_written_utf16_character_at_end_of_file_stays_in_the_unterminated_line()
+        {
+            var full = Bytes(Encoding.Unicode, "ok\r\nhalf");
+            var file = full.Concat(new byte[] { 0x41 }).ToArray(); // first byte of the next UTF-16 unit
+
+            var result = ReadAll(file);
+
+            Assert.Equal("ok", result.Lines[0]);
+            Assert.False(result.Terminated.Last());
+            Assert.Equal(file.Length, result.EndPositions.Last());
+        }
+
+        [Fact]
+        public void AlignDown_snaps_to_code_units_behind_the_byte_order_mark()
+        {
+            Assert.Equal(0, LogTextEncoding.Utf16LittleEndian.AlignDown(1));
+            Assert.Equal(2, LogTextEncoding.Utf16LittleEndian.AlignDown(3));
+            Assert.Equal(6, LogTextEncoding.Utf16LittleEndian.AlignDown(7));
+            Assert.Equal(8, LogTextEncoding.Utf32LittleEndian.AlignDown(11));
+            Assert.Equal(7, LogTextEncoding.Utf8.AlignDown(7));
+        }
+
+        [Fact]
+        public void Head_hash_of_a_prefix_matches_the_hash_of_the_shorter_file()
+        {
+            var shortFile = LogFileHead.FromBytes(Encoding.UTF8.GetBytes("2026-09-28 start"));
+            var grown = LogFileHead.FromBytes(Encoding.UTF8.GetBytes("2026-09-28 start\nmore lines"));
+
+            Assert.Equal(shortFile.Hash(shortFile.Length), grown.Hash(shortFile.Length));
+            Assert.NotEqual(shortFile.Hash(shortFile.Length), grown.Hash(grown.Length));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/LogParserCollectorDebugLogTests.cs

@@ -37,7 +37,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
                 logger, "sess", "tenant",
                 evt => _events.Add(evt),
                 null,
-                new LogFilePositionTracker(),
+                new GatherRuleSessionState("sess", null, logger),
                 new GatherRuleDebugLog(_debugLogPath, logger))
             {
                 UnrestrictedMode = true

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/LogParserCollectorReadingTests.cs

@@ -0,0 +1,225 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather.Collectors;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
+{
+    /// <summary>
+    /// Reading semantics of <see cref="LogParserCollector"/> across runs on one context: every
+    /// line of a growing log is matched exactly once — no line lost at a maxLines cut, no line
+    /// split by a writer that is mid-line, UTF-16 logs readable after the first run, positions
+    /// kept per rule, line numbers counted from the start of the file.
+    /// </summary>
+    public sealed class LogParserCollectorReadingTests : IDisposable
+    {
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly List<EnrollmentEvent> _events = new List<EnrollmentEvent>();
+        private readonly GatherRuleContext _context;
+
+        // %TEMP% lives under C:\Users (hard-blocked) — parse targets sit beside the
+        // test assembly instead, admitted via UnrestrictedMode.
+        private readonly string _logDir = Path.Combine(
+            AppContext.BaseDirectory, "gather-reading-tests-" + Guid.NewGuid().ToString("N"));
+
+        public LogParserCollectorReadingTests()
+        {
+            Directory.CreateDirectory(_logDir);
+            _context = NewContext();
+        }
+
+        public void Dispose()
+        {
+            _tmp.Dispose();
+            try { Directory.Delete(_logDir, recursive: true); } catch { /* best effort */ }
+        }
+
+        private GatherRuleContext NewContext()
+        {
+            var logger = new AgentLogger(_tmp.Path, AgentLogLevel.Info);
+            return new GatherRuleContext(logger, "sess", "tenant",
+                evt => _events.Add(evt), null, new GatherRuleSessionState("sess", null, logger))
+            {
+                UnrestrictedMode = true
+            };
+        }
+
+        private string LogPath(string name) => Path.Combine(_logDir, name);
+
+        private static GatherRule TextRule(string ruleId, string target, string pattern,
+            string trigger = "interval", int? maxLines = null)
+        {
+            var parameters = new Dictionary<string, string> { ["pattern"] = pattern, ["format"] = "text" };
+            if (maxLines.HasValue) parameters["maxLines"] = maxLines.Value.ToString();
+            return new GatherRule
+            {
+                RuleId = ruleId,
+                Title = ruleId,
+                CollectorType = "logparser",
+                Target = target,
+                Parameters = parameters,
+                Trigger = trigger,
+                IntervalSeconds = trigger == "interval" ? 30 : (int?)null,
+                OutputEventType = "logparser_reading_test",
+            };
+        }
+
+        private List<string> Captured(string group) =>
+            _events.Select(e => e.Data.TryGetValue(group, out var v) ? (string)v : "<missing>").ToList();
+
+        [Fact]
+        public void Two_rules_on_one_file_each_read_the_whole_file()
+        {
+            var path = LogPath("shared.log");
+            File.WriteAllText(path, "ERROR one\nWARN two\nERROR three\n");
+            var collector = new LogParserCollector();
+
+            collector.Execute(TextRule("RULE-ERRORS", path, "^ERROR (?<what>\\w+)"), _context);
+            collector.Execute(TextRule("RULE-WARNINGS", path, "^WARN (?<what>\\w+)"), _context);
+
+            Assert.Equal(2, _events.Count(e => (string)e.Data["ruleId"] == "RULE-ERRORS"));
+            Assert.Single(_events, e => (string)e.Data["ruleId"] == "RULE-WARNINGS");
+        }
+
+        [Fact]
+        public void MaxLines_cut_loses_no_line_across_runs()
+        {
+            var path = LogPath("long.log");
+            var sb = new StringBuilder();
+            for (var i = 1; i <= 30; i++)
+                sb.Append("hit ").Append(i.ToString("D3")).Append(' ').Append('x', 90).Append('\n');
+            File.WriteAllText(path, sb.ToString());
+            var rule = TextRule("RULE-LONG", path, "^hit (?<n>\\d{3})", maxLines: 10);
+            var collector = new LogParserCollector();
+
+            for (var run = 0; run < 6; run++)
+                collector.Execute(rule, _context);
+
+            var expected = Enumerable.Range(1, 30).Select(i => i.ToString("D3")).ToList();
+            Assert.Equal(expected, Captured("n"));
+        }
+
+        [Fact]
+        public void Line_written_in_two_parts_is_matched_once_and_whole()
+        {
+            var path = LogPath("partial.log");
+            File.WriteAllText(path, "ERR");
+            var rule = TextRule("RULE-PARTIAL", path, "^ERROR (?<code>0x[0-9A-F]+)$");
+            var collector = new LogParserCollector();
+
+            collector.Execute(rule, _context);          // the writer is mid-line
+            File.AppendAllText(path, "OR 0x1F\n");
+            collector.Execute(rule, _context);
+
+            Assert.Equal(new List<string> { "0x1F" }, Captured("code"));
+        }
+
+        [Fact]
+        public void Interval_rule_reads_a_line_still_unfinished_on_its_second_run_once()
+        {
+            var path = LogPath("never-terminated.log");
+            File.WriteAllText(path, "ERROR 0x2A");
+            var rule = TextRule("RULE-UNFINISHED", path, "^ERROR (?<code>0x[0-9A-F]+)$");
+            var collector = new LogParserCollector();
+
+            collector.Execute(rule, _context);   // held: the writer may still be in the line
+            collector.Execute(rule, _context);   // still unfinished — taken as it is
+            collector.Execute(rule, _context);   // nothing new
+
+            Assert.Equal(new List<string> { "0x2A" }, Captured("code"));
+        }
+
+        [Fact]
+        public void One_shot_rule_reads_an_unfinished_line_now_and_whole_on_its_next_run()
+        {
+            var path = LogPath("startup.log");
+            File.WriteAllText(path, "ok\nERR");
+            var rule = TextRule("RULE-STARTUP", path, "^ERR(?<rest>.*)$", trigger: "startup");
+            var collector = new LogParserCollector();
+
+            collector.Execute(rule, _context);   // agent start: the writer is mid-line
+            File.AppendAllText(path, "OR 0x1F\n");
+            collector.Execute(rule, _context);   // next agent start
+
+            // Read twice, never split: the second read sees the whole line.
+            Assert.Equal(new List<string> { "", "OR 0x1F" }, Captured("rest"));
+            Assert.Equal(new long[] { 2, 2 }, _events.Select(e => Convert.ToInt64(e.Data["logLineNumber"])).ToArray());
+        }
+
+        [Fact]
+        public void Line_feed_written_after_a_trailing_carriage_return_is_consumed_without_a_line()
+        {
+            var path = LogPath("cr-at-end.log");
+            File.WriteAllText(path, "hit\r");
+            var rule = TextRule("RULE-CR", path, "^hit$");
+            var collector = new LogParserCollector();
+
+            collector.Execute(rule, _context);
+            File.AppendAllText(path, "\n");
+            collector.Execute(rule, _context);
+
+            Assert.Single(_events);
+            var position = _context.SessionState.PeekLogPosition("RULE-CR", path);
+            Assert.Equal(new FileInfo(path).Length, position!.Position);
+            Assert.Equal(1, position.LineNumber);
+        }
+
+        [Fact]
+        public void Utf16_log_appended_after_the_first_run_is_still_matched()
+        {
+            var path = LogPath("transcript.log");
+            File.WriteAllText(path, "ERROR first\r\n", Encoding.Unicode);   // UTF-16 LE with BOM
+            var rule = TextRule("RULE-UTF16", path, "^ERROR (?<what>\\w+)$");
+            var collector = new LogParserCollector();
+
+            collector.Execute(rule, _context);
+            using (var stream = new FileStream(path, FileMode.Append, FileAccess.Write))
+            {
+                var bytes = new UnicodeEncoding(bigEndian: false, byteOrderMark: false).GetBytes("ERROR second\r\n");
+                stream.Write(bytes, 0, bytes.Length);
+            }
+            collector.Execute(rule, _context);
+
+            Assert.Equal(new List<string> { "first", "second" }, Captured("what"));
+        }
+
+        [Theory]
+        [InlineData("abc")]
+        [InlineData("0")]
+        [InlineData("-5")]
+        public void MaxLines_that_is_no_positive_number_falls_back_to_the_default(string maxLines)
+        {
+            var path = LogPath("misconfigured.log");
+            File.WriteAllText(path, "hit 1\nhit 2\n");
+            var rule = TextRule("RULE-MISCONFIGURED", path, "^hit (?<n>\\d)$");
+            rule.Parameters["maxLines"] = maxLines;
+
+            new LogParserCollector().Execute(rule, _context);
+
+            Assert.Equal(new List<string> { "1", "2" }, Captured("n"));
+        }
+
+        [Fact]
+        public void Line_numbers_count_from_the_start_of_the_file()
+        {
+            var path = LogPath("numbers.log");
+            File.WriteAllText(path, "a\nhit\nb\n");
+            var rule = TextRule("RULE-NUMBERS", path, "^hit$");
+            var collector = new LogParserCollector();
+
+            collector.Execute(rule, _context);
+            File.AppendAllText(path, "c\nhit\n");
+            collector.Execute(rule, _context);
+
+            Assert.Equal(new long[] { 2, 5 }, _events.Select(e => Convert.ToInt64(e.Data["logLineNumber"])).ToArray());
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Gather/RegistryCollectorEmitOnlyIfExistsTests.cs

@@ -35,7 +35,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Gather
                 tenantId: "tenant",
                 onEventCollected: _ => { },
                 imeLogPathOverride: null,
-                filePositionTracker: new LogFilePositionTracker())
+                sessionState: new GatherRuleSessionState("sess", null, logger))
             {
                 // Bypass the registry allowlist guard for the synthetic test path.
                 UnrestrictedMode = true

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/HelloTrackerCompletionBudgetTests.cs

@@ -0,0 +1,71 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.Shared;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
+{
+    /// <summary>
+    /// The completion timer a started Hello wizard runs against is the tenant's Hello wait
+    /// (<c>HelloWaitTimeoutSeconds</c>), resolved to 300..3600 s — the same budget the engine's
+    /// hello_safety window spends from the ESP exit, so a tenant allowing an hour is not cut off
+    /// by a fixed 5-min tracker timer while the user is still inside the wizard.
+    /// </summary>
+    public sealed class HelloTrackerCompletionBudgetTests
+    {
+        private static readonly DateTime Fixed = new DateTime(2026, 9, 29, 8, 0, 0, DateTimeKind.Utc);
+
+        [Theory]
+        [InlineData(30, 300)]     // the old default, still stored for many tenants → the built-in window
+        [InlineData(0, 300)]
+        [InlineData(300, 300)]
+        [InlineData(1800, 1800)]
+        [InlineData(3600, 3600)]
+        [InlineData(86400, 3600)] // clamped to the ceiling
+        public void Completion_budget_is_the_resolved_tenant_hello_wait(int configured, int expected)
+        {
+            using var tmp = new TempDirectory();
+            using var tracker = NewTracker(tmp, new FakeSignalIngressSink(), configured);
+
+            Assert.Equal(expected, tracker.CompletionTimeoutSecondsForTest);
+        }
+
+        [Fact]
+        public void Completion_timeout_event_reports_the_tenant_budget()
+        {
+            using var tmp = new TempDirectory();
+            var ingress = new FakeSignalIngressSink();
+            using var tracker = NewTracker(tmp, ingress, helloWaitTimeoutSeconds: 2400);
+
+            tracker.NotifyHelloWizardStarted();
+            Assert.True(tracker.IsCompletionTimerActiveForTest);
+            tracker.TriggerCompletionTimeoutForTest();
+
+            var timeout = ingress.Posted.Single(p =>
+                p.Kind == DecisionSignalKind.InformationalEvent
+                && p.Payload != null
+                && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                && et == Constants.EventTypes.HelloCompletionTimeout);
+            var data = Assert.IsAssignableFrom<IDictionary<string, object>>(timeout.TypedPayload);
+            Assert.Equal(2400, data["timeoutSeconds"]);
+            Assert.Equal("timeout", tracker.HelloOutcome);
+        }
+
+        private static HelloTracker NewTracker(TempDirectory tmp, FakeSignalIngressSink ingress, int helloWaitTimeoutSeconds) =>
+            new HelloTracker(
+                sessionId: "S1",
+                tenantId: "T1",
+                post: new InformationalEventPost(ingress, new VirtualClock(Fixed)),
+                logger: new AgentLogger(tmp.Path, AgentLogLevel.Info),
+                helloWaitTimeoutSeconds: helloWaitTimeoutSeconds);
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/CmTraceOffsetCalibratorTests.cs

@@ -186,5 +186,20 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             DateTime resolved;
             Assert.False(sut.TryResolveUtc(Source, UtcNow, out resolved));
         }
+
+        [Theory]
+        [InlineData(3610.39, true, 4)]     // session 4377911b: +1 h on a 10 s script
+        [InlineData(61203.0, true, 68)]    // 17 h on a 3 s script
+        [InlineData(7205.66, true, 8)]     // session cbaed57b: +2 h
+        [InlineData(-3596.0, true, 4)]     // the same error on the start end
+        [InlineData(26.4, false, 0)]       // a run time below one grid step
+        [InlineData(1030.0, false, 1)]     // 17 min 10 s: residual past the tolerance
+        [InlineData(900.0, true, 1)]       // exactly one step — a genuine 15-minute run reads the same, the caller needs mixed provenance too
+        public void A_grid_sized_span_is_the_signature_of_an_offset_error(double seconds, bool onGrid, int expectedSteps)
+        {
+            int steps;
+            Assert.Equal(onGrid, CmTraceOffsetCalibrator.IsOnOffsetGrid(TimeSpan.FromSeconds(seconds), out steps));
+            if (onGrid) Assert.Equal(expectedSteps, steps);
+        }
     }
 }

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogPatternPackLinearityTests.cs

@@ -337,7 +337,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
                 "Launch powershell executor in machine session",
                 new[] { "context=machine" }
             };
-            // Wording from the IME decompile (ContentDownloaderDeliveryOptimization, identical 1.97–1.105).
+            // IME wording, identical from 1.97 to 1.105.
             yield return new object[]
             {
                 "IME-DO-TIMEOUT-2",

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerHealthTests.cs

@@ -140,6 +140,22 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.Equal(1, fired); // the persisted flag suppressed the second emission
         }
 
+        [Fact]
+        public void Registry_reconciliation_counters_survive_a_restart()
+        {
+            using var h = new Harness();
+            h.Tracker.ScriptRuns.CountVerified();
+            h.Tracker.ScriptRuns.CountVerified();
+            h.Tracker.ScriptRuns.CountCorrected();
+            h.Tracker.SaveStateForTest();
+
+            h.Restart();
+
+            var health = h.Tracker.GetHealthSnapshot();
+            Assert.Equal(2, health.PlatformOutputVerified);
+            Assert.Equal(1, health.PlatformOutputCorrected);
+        }
+
         [Fact]
         public async Task Handler_time_does_not_count_against_the_line_budget()
         {

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.RetryPairing.cs

@@ -0,0 +1,336 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// B-96m: IME re-runs a failed platform script on later check-ins, so AgentExecutor.log can hold several runs of one
+    /// policy before the tracker has read IME's result of the first — always on the agent's first pass (the agent starts
+    /// mid-enrollment and reads all of AgentExecutor.log before IntuneManagementExtension.log), after a restart, and
+    /// whenever a result line surfaces late. With one slot per policy the second executor start reused the first run's
+    /// slot and its end block overwrote the first one: the first IME result went out with the LAST run's exit code and
+    /// output (session eff1b413: the bootstrap script "Failed (exit 0)" with the stdout of its successful retry), every
+    /// later result without an end block. These tests pin one run per executor start, each IME result paired with the
+    /// run of its policy that started last before it, each run carrying its own end block.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private const string RetryPolicyId = "4c2d8e1a-7b3f-4a9e-8d21-6f0b5c3e9a74";
+        private const string RetryUser = "00000000-0000-0000-0000-000000000000";
+
+        private static string ImeEntryAt(string time, string message)
+            => $"<![LOG[{message}]LOG]!><time=\"{time}\" date=\"9-10-2026\" component=\"IntuneManagementExtension\" context=\"\" type=\"1\" thread=\"12\" file=\"\">\r\n";
+
+        /// <summary>One executor run's start block: banner, the platform argument line, paths, launch.</summary>
+        private static string RunStart(string time, string pid, string policyId = RetryPolicyId, string userId = RetryUser)
+        {
+            var path = $@"{ImeDir}\Policies\Scripts\{userId}_{policyId}.ps1";
+            var results = $@"{ImeDir}\Policies\Results\{userId}_{policyId}";
+            return ExecutorBanner(time)
+                + EntryAt(time, $"Adding argument powershell with value {path} to the named argument list.")
+                + EntryAt(time, "Powershell option gets invoked")
+                + EntryAt(time, path)
+                + EntryAt(time, results + ".output")
+                + EntryAt(time, results + ".error")
+                + EntryAt(time, results + ".timeout")
+                + ExecutorLaunch(time, path, pid);
+        }
+
+        /// <summary>
+        /// One executor run's end block in AgentExecutor's order. "error from script =" logs the stderr buffer before the
+        /// output readers finished (<paramref name="stderrSnapshot"/>); "write output done" logs the final texts, the
+        /// error part being exactly the error file IME judges.
+        /// </summary>
+        private static string RunEnd(string time, int exitCode, string stdout, string stderr, string? stderrSnapshot = null)
+            => EntryAt(time, $"Powershell exit code is {exitCode}")
+            + EntryAt(time, $"length of out={stdout.Length}")
+            + EntryAt(time, $"length of error={stderr.Length}")
+            + EntryAt(time, "error from script =" + (stderrSnapshot ?? stderr))
+            + EntryAt(time, exitCode == 0 ? "Powershell script is successfully executed." : "Powershell script is failed to execute")
+            + EntryAt(time, $"write output done. output = {stdout}, error = {stderr}")
+            + EntryAt(time, "Revert Wow64FsRedirection")
+            + EntryAt(time, "Agent executor completed.");
+
+        private static string ImeRunStart(string time, string policyId = RetryPolicyId, string userId = RetryUser)
+            => ImeEntryAt(time, $@"Script file {ImeDir}\Policies\Scripts\{userId}_{policyId}.ps1 is generated.");
+
+        private static string ImeRunResult(string time, string result, string policyId = RetryPolicyId, string userId = RetryUser)
+            => ImeEntryAt(time, $"[PowerShell] User Id = {userId}, Policy id = {policyId}, policy result = {result}");
+
+        private static void AppendImeLog(Harness h, string text)
+            => File.AppendAllText(Path.Combine(Path.GetDirectoryName(h.LogPath)!, "IntuneManagementExtension.log"), text, new UTF8Encoding(false));
+
+        /// <summary>Result | exit | stdout | stderr — readable in an assertion failure; "-" no exit code, "~" never read.</summary>
+        private static string Shape(ScriptExecutionState s)
+            => $"{s.Result}|{(s.ExitCode.HasValue ? s.ExitCode.Value.ToString() : "-")}|{s.Stdout ?? "~"}|{s.Stderr ?? "~"}";
+
+        /// <summary>
+        /// Two poll passes as the agent runs them (read the files, then the flushes), the second past the result hold:
+        /// a result missing its end block goes out by then.
+        /// </summary>
+        private static async Task PassAndSettle(Harness h)
+        {
+            await h.Tracker.RunPollPassAsync(default);
+            h.Now = h.Now.AddSeconds(6);
+            await h.Tracker.RunPollPassAsync(default);
+        }
+
+        [Fact]
+        public async Task First_pass_pairs_each_ime_result_with_the_end_block_of_its_own_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            // IME's first run and two retries on later check-ins, all written before the agent started.
+            h.Append(RunStart("12:00:10.0000000", "1001") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "1002") + RunEnd("12:10:12.0000000", 1, "Run B output", "")
+                + RunStart("12:20:10.0000000", "1003") + RunEnd("12:20:12.0000000", 0, "Run C output", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success")
+                + ImeRunStart("12:20:08.0000000") + ImeRunResult("12:20:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|1||Run A failed", "Success|1|Run B output|", "Success|0|Run C output|" },
+                h.Completed.Select(Shape).ToArray());
+            Assert.All(h.Completed, s => Assert.Equal("ime_policy_result", s.ResultSource));
+            Assert.True(h.Completed[0].StartedAtUtc < h.Completed[1].StartedAtUtc && h.Completed[1].StartedAtUtc < h.Completed[2].StartedAtUtc);
+            Assert.Equal(3, h.Completed.Select(s => s.RunId).Distinct().Count());
+        }
+
+        [Fact]
+        public async Task Retry_of_the_bootstrap_script_never_lends_its_success_output_to_the_failed_first_attempt()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "2001") + RunEnd("12:00:20.0000000", 1, "attempt 1: download failed", "Invoke-WebRequest : The remote name could not be resolved")
+                + RunStart("12:10:10.0000000", "2002") + RunEnd("12:10:20.0000000", 0, "===== Bootstrap Completed Successfully =====", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:20.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:20.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[]
+            {
+                "Failed|1|attempt 1: download failed|Invoke-WebRequest : The remote name could not be resolved",
+                "Success|0|===== Bootstrap Completed Successfully =====|",
+            }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_killed_at_the_timeout_reports_failed_without_the_next_runs_end_block()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            // IME killed the first executor after 1800 s: its start block is all AgentExecutor.log holds of it.
+            h.Append(RunStart("12:00:10.0000000", "3001")
+                + RunStart("12:40:10.0000000", "3002") + RunEnd("12:40:12.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:30:10.5000000", "Failed")
+                + ImeRunStart("12:40:08.0000000") + ImeRunResult("12:40:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|-|~|~", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_whose_result_never_surfaced_falls_back_on_imes_rule_before_the_next_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "4001") + RunEnd("12:00:12.0000000", 0, "Run A output", "Run A wrote an error")
+                + RunStart("12:10:10.0000000", "4002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            // Run A's result line was lost; run B's is there.
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|0|Run A output|Run A wrote an error", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+            Assert.Equal(new[] { "agentexecutor_fallback", "ime_policy_result" }, h.Completed.Select(s => s.ResultSource).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_in_flight_survives_the_emit_of_the_run_before_it()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "5001") + RunEnd("12:00:12.0000000", 0, "Run A output", "")
+                + RunStart("12:10:10.0000000", "5002"));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Success") + ImeRunStart("12:10:08.0000000"));
+            await PassAndSettle(h);
+            h.Now = h.Now.AddSeconds(30);
+            await h.Pass();
+
+            // Run B ends minutes later.
+            h.Append(RunEnd("12:10:40.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunResult("12:10:40.1000000", "Success"));
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Success|0|Run A output|", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Shutdown_between_the_two_logs_flushes_each_run_with_its_own_end_block()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "6001") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "6002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            // The pass is cancelled after AgentExecutor.log; the shutdown flush follows.
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now, force: true);
+
+            h.Restart();
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+            await PassAndSettle(h);
+
+            // Each run went out with its own block and IME's verdict on it; the results read after the restart are
+            // the same runs and change nothing.
+            Assert.Equal(new[] { "Failed|1||Run A failed", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+            Assert.All(h.Completed, s => Assert.Equal("agentexecutor_fallback", s.ResultSource));
+        }
+
+        [Fact]
+        public async Task End_block_line_recovered_after_the_next_run_started_stays_with_its_own_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "7001"));
+            var exitLineAt = h.Length;
+            h.Append(RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "7002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            await h.Pass();
+
+            // A stale writer rewrites run A's exit line in place: the ledger check re-reads it behind run B's start.
+            h.Overwrite(exitLineAt, EntryAt("12:00:12.0000000", "Powershell exit code is 7"));
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddSeconds(2);
+            await h.Pass();
+
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|7||Run A failed", "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Run_without_result_or_end_block_is_dropped_once_a_later_run_has_its_result()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9001")
+                + RunStart("12:10:10.0000000", "9002") + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunStart("12:10:08.0000000") + ImeRunResult("12:10:12.1000000", "Success"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Success|0|Run B output|" }, h.Completed.Select(Shape).ToArray());
+            Assert.Equal(0, h.Tracker.ParkedPlatformScriptCountForTest);
+        }
+
+        [Fact]
+        public void Reading_the_same_executor_start_line_again_never_parks_its_run()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            var line = $@"Adding argument powershell with value {ImeDir}\Policies\Scripts\{RetryUser}_{RetryPolicyId}.ps1 to the named argument list.";
+            var at = T0.AddMinutes(-30);
+
+            h.Tracker.ProcessLogMessageForTest(line, at, "AgentExecutor.log");
+            h.Tracker.ProcessLogMessageForTest(line, at, "AgentExecutor.log");
+            Assert.Equal(0, h.Tracker.ParkedPlatformScriptCountForTest);
+
+            h.Tracker.ProcessLogMessageForTest(line, at.AddMinutes(10), "AgentExecutor.log");
+            Assert.Equal(1, h.Tracker.ParkedPlatformScriptCountForTest);
+        }
+
+        [Fact]
+        public async Task Run_without_end_block_keeps_waiting_for_its_result_across_a_shutdown()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9101") + RunStart("12:40:10.0000000", "9102"));
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now, force: true);
+            Assert.Empty(h.Completed);
+
+            h.Restart();
+            Assert.Equal(1, h.Tracker.ParkedPlatformScriptCountForTest);
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:30:10.5000000", "Failed"));
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|-|~|~" }, h.Completed.Select(Shape).ToArray());
+        }
+
+        [Fact]
+        public async Task Earlier_run_emitted_while_a_later_one_runs_never_takes_the_later_runs_register_entry()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9201") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "9202"));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed") + ImeRunStart("12:10:08.0000000"));
+            await PassAndSettle(h);
+            Assert.Single(h.Completed);
+
+            // A save of this key is the latest run's, and that one is still running.
+            h.Tracker.ScriptRuns.NotePassCompleted(h.Now);
+            Assert.Equal(PlatformRunClaim.Wait, h.Tracker.ScriptRuns.TryClaim(RetryUser, RetryPolicyId, h.Now.AddSeconds(-10), out _));
+
+            h.Append(RunEnd("12:10:40.0000000", 0, "Run B output", ""));
+            AppendImeLog(h, ImeRunResult("12:10:40.1000000", "Success"));
+            await PassAndSettle(h);
+            h.Tracker.ScriptRuns.NotePassCompleted(h.Now);
+
+            Assert.Equal(PlatformRunClaim.Claimed, h.Tracker.ScriptRuns.TryClaim(RetryUser, RetryPolicyId, h.Now.AddSeconds(-10), out var run));
+            Assert.Equal(h.Completed[1].RunId, run!.RunId);
+            Assert.Equal("Run B output", run.Stdout);
+        }
+
+        [Fact]
+        public async Task Run_of_another_user_keeps_its_own_register_entry_when_it_waited_for_its_result()
+        {
+            const string otherUser = "2b7e5c91-3d4a-4f80-b6e2-9a1c7d3f5e08";
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9301") + RunEnd("12:00:12.0000000", 1, "", "Run A failed")
+                + RunStart("12:10:10.0000000", "9302", userId: otherUser));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed")
+                + ImeRunStart("12:10:08.0000000", userId: otherUser));
+            await PassAndSettle(h);
+            h.Tracker.ScriptRuns.NotePassCompleted(h.Now);
+
+            Assert.Equal(PlatformRunClaim.Claimed, h.Tracker.ScriptRuns.TryClaim(RetryUser, RetryPolicyId, h.Now.AddSeconds(-10), out var run));
+            Assert.Equal(h.Completed[0].RunId, run!.RunId);
+            Assert.Equal(PlatformRunClaim.Wait, h.Tracker.ScriptRuns.TryClaim(otherUser, RetryPolicyId, h.Now.AddSeconds(-10), out _));
+        }
+
+        [Fact]
+        public async Task Start_line_read_again_stays_a_late_line_after_an_earlier_run_of_another_user_went_out()
+        {
+            const string otherUser = "2b7e5c91-3d4a-4f80-b6e2-9a1c7d3f5e08";
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(RunStart("12:00:10.0000000", "9401") + RunEnd("12:00:12.0000000", 0, "Run A output", "")
+                + RunStart("12:10:10.0000000", "9402", userId: otherUser) + RunEnd("12:10:12.0000000", 0, "Run B output", ""));
+            // Run A's result surfaces after run B's (its line was hidden by a concurrent writer).
+            AppendImeLog(h, ImeRunResult("12:10:12.1000000", "Success", userId: otherUser) + ImeRunResult("12:00:12.1000000", "Success"));
+            await PassAndSettle(h);
+            Assert.Equal(new[] { "Success|0|Run B output|", "Success|0|Run A output|" }, h.Completed.Select(Shape).ToArray());
+
+            // Run B's executor start line read again (a rewind): a late line of the emitted run B, never a new run.
+            var started = 0;
+            h.Tracker.OnScriptStarted = _ => started++;
+            h.Tracker.ProcessLogMessageForTest(
+                $@"Adding argument powershell with value {ImeDir}\Policies\Scripts\{otherUser}_{RetryPolicyId}.ps1 to the named argument list.",
+                h.Completed[0].StartedAtUtc, "AgentExecutor.log");
+            Assert.Equal(0, started);
+        }
+
+        [Fact]
+        public async Task Final_stderr_of_the_end_block_replaces_the_early_snapshot_even_without_stdout()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            // The snapshot was taken before the error reader finished; IME judged the full error file.
+            h.Append(RunStart("12:00:10.0000000", "8001") + RunEnd("12:00:12.0000000", 0, "", "Remove-AppxPackage : Cannot process argument", stderrSnapshot: ""));
+            AppendImeLog(h, ImeRunStart("12:00:08.0000000") + ImeRunResult("12:00:12.1000000", "Failed"));
+
+            await PassAndSettle(h);
+
+            Assert.Equal(new[] { "Failed|0||Remove-AppxPackage : Cannot process argument" }, h.Completed.Select(Shape).ToArray());
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.RewindFreshness.cs

@@ -0,0 +1,139 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.SignalAdapters;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// Sessions d29e27e3 and 4377911b: a concurrent IME writer overwrote the result line of a platform script, and the
+    /// overwrite check recovered it one pass later. Recovered lines were never fresh, so they resolved in the agent's own
+    /// cached zone (+60) instead of anchoring themselves (+120): the end stamp landed an hour ahead of the clock and the
+    /// run duration was omitted. Bytes that read differently at a position than at the last look were written after that
+    /// look, so when the replaced bytes were confirmed seconds ago the new line's age is bounded like an appended line's —
+    /// these tests pin that it anchors itself then, and only then.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private static void AppendExecutorLog(Harness h, string text)
+            => File.AppendAllText(Path.Combine(Path.GetDirectoryName(h.LogPath)!, "AgentExecutor.log"), text, new UTF8Encoding(false));
+
+        /// <summary>An IME log entry with the byte length of <paramref name="sameLengthAs"/>: what a stale writer's line replaces exactly.</summary>
+        private static string FillerLike(string time, string sameLengthAs)
+        {
+            var bare = ImeEntryAt(time, "[Win32App] checking ");
+            Assert.True(sameLengthAs.Length > bare.Length);
+            return ImeEntryAt(time, "[Win32App] checking " + new string('x', sameLengthAs.Length - bare.Length));
+        }
+
+        /// <summary>
+        /// A platform run whose IME writer lives in +120 (local = UTC + 2 h; the harness clock is 19:30Z): both logs are
+        /// observed empty first, so what follows is read fresh. Returns the IME log position where the filler line sits.
+        /// </summary>
+        private static async Task<long> StartRunAndReadFiller(Harness h, string fillerTime, string resultEntry)
+        {
+            h.Append(string.Empty);
+            AppendExecutorLog(h, string.Empty);
+            await h.Tracker.RunPollPassAsync(default);
+
+            AppendExecutorLog(h, RunStart("21:29:50.0000000", "1001"));
+            h.Append(ImeRunStart("21:29:48.0000000"));
+            await h.Tracker.RunPollPassAsync(default);
+
+            // Another IME writer appends a line; the tracker reads it.
+            var at = h.Length;
+            h.Append(FillerLike(fillerTime, resultEntry));
+            h.Now = h.Now.AddSeconds(1);
+            await h.Tracker.RunPollPassAsync(default);
+            return at;
+        }
+
+        [Fact]
+        public async Task Result_line_recovered_seconds_after_its_bytes_were_read_anchors_itself_like_a_fresh_line()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            var result = ImeRunResult("21:30:01.1000000", "Success");
+            var at = await StartRunAndReadFiller(h, "21:30:00.5000000", result);
+
+            // The script ends: its end block, then the stale IME service writes the result over the filler.
+            AppendExecutorLog(h, RunEnd("21:30:01.0000000", 0, "done", ""));
+            h.Overwrite(at, result);
+            h.Now = h.Now.AddSeconds(1);
+            await PassAndSettle(h);
+
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(CmTraceOffsetOrigin.LineAnchored, script.ResultProvenance!.Origin);
+            Assert.Equal(120, script.ResultProvenance.OffsetMinutes);
+            Assert.Equal(ImeLogTrackerAdapter.DurationPairVerdict.Verified, ImeLogTrackerAdapter.JudgeDurationPair(
+                script.StartedAtProvenance, script.ResultProvenance, false, script.ResultObservedAtUtc!.Value - script.StartedAtUtc!.Value, out _));
+        }
+
+        [Fact]
+        public async Task Verification_passes_keep_the_replaced_bytes_current_for_a_script_that_runs_longer()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            var result = ImeRunResult("21:30:41.1000000", "Success");
+            var at = await StartRunAndReadFiller(h, "21:30:00.5000000", result);
+
+            // The script runs 40 s; the cadence check verifies the ledger every 10 s while the run is in flight.
+            for (var i = 0; i < 4; i++)
+            {
+                h.Now = h.Now.AddSeconds(10);
+                await h.Tracker.RunPollPassAsync(default);
+            }
+
+            AppendExecutorLog(h, RunEnd("21:30:41.0000000", 0, "done", ""));
+            h.Overwrite(at, result);
+            h.Now = h.Now.AddSeconds(1);
+            await PassAndSettle(h);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(CmTraceOffsetOrigin.LineAnchored, script.ResultProvenance!.Origin);
+            Assert.Equal(120, script.ResultProvenance.OffsetMinutes);
+        }
+
+        [Fact]
+        public async Task Overwrite_does_not_move_the_files_measured_writer_offset()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            var result = ImeRunResult("21:30:01.1000000", "Success");
+            var at = await StartRunAndReadFiller(h, "21:30:00.5000000", result);
+            Assert.True(h.Tracker.OffsetCalibrator.TryGetOffset("IntuneManagementExtension.log", out var before));
+
+            AppendExecutorLog(h, RunEnd("21:30:01.0000000", 0, "done", ""));
+            h.Overwrite(at, result);
+            h.Now = h.Now.AddSeconds(1);
+            await PassAndSettle(h);
+
+            Assert.True(h.Tracker.OffsetCalibrator.TryGetOffset("IntuneManagementExtension.log", out var after));
+            Assert.Equal(before, after);
+        }
+
+        [Theory]
+        // Replaced bytes confirmed 1 s / 30 s ago: written since, age bounded like an appended line's.
+        [InlineData(true, true, 1, true)]
+        [InlineData(true, true, 30, true)]
+        // Confirmed longer ago: the new bytes could be minutes old — their age may round onto the 15-minute grid.
+        [InlineData(true, true, 31, false)]
+        // The clock stepped back since the confirmation: the age is unknown.
+        [InlineData(true, true, -1, false)]
+        // The divergence lies in bytes the ledger never held (dropped by a cap): nothing dates them.
+        [InlineData(true, false, 1, false)]
+        // The pass itself is not fresh — the first pass after a restart never anchors.
+        [InlineData(false, true, 1, false)]
+        // Nothing was replaced.
+        [InlineData(true, true, null, false)]
+        public void Rewound_entry_is_fresh_only_when_the_bytes_it_replaced_were_confirmed_within_the_fresh_window(
+            bool passLinesAreFresh, bool entryAtRewindPointReplaced, int? secondsSinceConfirmed, bool expected)
+        {
+            var now = new DateTime(2026, 10, 4, 19, 2, 0, DateTimeKind.Utc);
+            DateTime? confirmed = secondsSinceConfirmed.HasValue ? now.AddSeconds(-secondsSinceConfirmed.Value) : (DateTime?)null;
+            Assert.Equal(expected, ImeLogTracker.RewoundEntryIsFresh(passLinesAreFresh, entryAtRewindPointReplaced, confirmed, now));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.WriterBoundary.cs

@@ -0,0 +1,368 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// Session 756970cf: IME launched a Win32 detection executor and a platform-script executor 15 ms apart, and both
+    /// opened AgentExecutor.log at the same end-of-file offset. The platform executor's shorter start block overwrote
+    /// the detection executor's, whose identity line the tracker never saw; the detection's end block (exit 1 and its
+    /// stdout), written at its own position behind its own start block, then sat behind the PLATFORM start block, and
+    /// "the nearest preceding marker owns the line" handed another script's output and exit code to the platform
+    /// script. These tests pin the writer boundary: an entry that is not exactly one CMTrace record is where one
+    /// writer's bytes end and another's begin, and nothing behind it belongs to the invocation in front of it.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private const string RaceUserId = "00000000-0000-0000-0000-000000000000";
+        private const string RacePlatformId = "1d6f0a52-3c4e-4b7a-9e21-5f8c7d2b9a10";
+        private const string RaceDetectionAppId = "8b2e4c71-6a9d-4f03-b5e8-2c7a1d9f4e36";
+        private const string RaceFillerAppId = "5e1c2b7d-0a4f-4c8e-9d36-7b2f1e8a4c50";
+        private const string ImeDir = @"C:\Program Files (x86)\Microsoft Intune Management Extension";
+        private const string DetectionStdout = "VERBOSE: === Sample Suite Detection Started ===\r\nWARNING: === DETECTION FAILED: Sample Suite is not installed ===";
+        private const string PlatformStdout = "=== bootstrap loader started ===\r\nInstaller finished (exit code 0).";
+
+        private static string EntryAt(string time, string message)
+            => $"<![LOG[{message}]LOG]!><time=\"{time}\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">\r\n";
+
+        /// <summary>The four lines every AgentExecutor invocation starts with — identical length for every executor.</summary>
+        private static string ExecutorBanner(string time)
+            => EntryAt(time, "ExecutorLog AgentExecutor gets invoked")
+            + EntryAt(time, "Creating command line parser, name delimiter is - and value separator is  .")
+            + EntryAt(time, "Getting Ordered Parameters")
+            + EntryAt(time, "Parsing Ordered Parameters.");
+
+        private static string ExecutorLaunch(string time, string scriptPath, string pid)
+            => EntryAt(time, "Prepare to run Powershell Script ..")
+            + EntryAt(time, $"cmd line for running powershell is -NoProfile -executionPolicy bypass -file  \"{scriptPath}\" ")
+            + EntryAt(time, "runAs32BitOn64 = False, so Disable Wow64FsRedirection")
+            + EntryAt(time, @"PowerShell path is C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe")
+            + EntryAt(time, $"[Executor] created powershell with process id {pid}");
+
+        private static string PlatformStartBlock(string time, string policyId, string pid)
+        {
+            var path = $@"{ImeDir}\Policies\Scripts\{RaceUserId}_{policyId}.ps1";
+            var results = $@"{ImeDir}\Policies\Results\{RaceUserId}_{policyId}";
+            return ExecutorBanner(time)
+                + EntryAt(time, $"Adding argument powershell with value {path} to the named argument list.")
+                + EntryAt(time, "Powershell option gets invoked")
+                + EntryAt(time, path)
+                + EntryAt(time, results + ".output")
+                + EntryAt(time, results + ".error")
+                + EntryAt(time, results + ".timeout")
+                + ExecutorLaunch(time, path, pid);
+        }
+
+        private static string DetectionStartBlock(string time, string appId, string pid)
+        {
+            var path = $@"{ImeDir}\Content\DetectionScripts\{appId}_2.ps1";
+            return ExecutorBanner(time)
+                + EntryAt(time, $"Adding argument powershellDetection with value {path} to the named argument list.")
+                + EntryAt(time, "PowershellDetection option gets invoked")
+                + EntryAt(time, path)
+                + EntryAt(time, path + "quotedResultFilePath.txt")
+                + EntryAt(time, path + "quotedErrorFilePath.txt")
+                + EntryAt(time, path + "quotedTimeoutFilePath.txt")
+                + EntryAt(time, path + "quotedExitCodeFilePath.txt")
+                + ExecutorLaunch(time, path, pid);
+        }
+
+        private static string ExecutorEndBlock(string time, int exitCode, string stdout)
+            => EntryAt(time, $"Powershell exit code is {exitCode}")
+            + EntryAt(time, $"length of out={stdout.Length}")
+            + EntryAt(time, "length of error=0")
+            + EntryAt(time, "error from script =")
+            + EntryAt(time, exitCode == 0 ? "Powershell script is successfully executed." : "Powershell script is failed to execute")
+            + EntryAt(time, $"write output done. output = {stdout}, error = ")
+            + EntryAt(time, "Revert Wow64FsRedirection")
+            + EntryAt(time, "Agent executor completed.");
+
+        private static string PlatformResultLine(string policyId)
+            => $"[PowerShell] User Id = {RaceUserId}, Policy id = {policyId}, policy result = Success";
+
+        /// <summary>The file offsets at which the entries of an ASCII <paramref name="block"/> start when it is written at <paramref name="at"/>.</summary>
+        private static HashSet<long> EntryStarts(string block, long at)
+        {
+            Assert.True(block.All(c => c < 128), "offset arithmetic assumes ASCII test content");
+            var starts = new HashSet<long>();
+            for (var i = block.IndexOf("<![LOG[", StringComparison.Ordinal); i >= 0; i = block.IndexOf("<![LOG[", i + 1, StringComparison.Ordinal))
+                starts.Add(at + i);
+            return starts;
+        }
+
+        [Fact]
+        public async Task Executor_that_opened_at_the_same_offset_never_lends_its_end_block_to_the_platform_script()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // An earlier, finished detection run: the race starts mid-file like in the field log.
+            h.Append(DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1548") + ExecutorEndBlock("12:00:00.5000000", 0, "detected"));
+            await h.Pass();
+            var x = h.Length;
+
+            // Detection executor C and platform executor D open the file at the same end x. C writes first; the tracker
+            // reads C's banner, then D writes its own start block over C's.
+            var cStart = DetectionStartBlock("12:00:01.0000000", RaceDetectionAppId, "6416");
+            var dStart = PlatformStartBlock("12:00:01.2000000", RacePlatformId, "2524");
+            var cHead = cStart.Substring(0, cStart.IndexOf("<![LOG[Getting Ordered Parameters", StringComparison.Ordinal));
+            h.Append(cHead);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Append(cStart.Substring(cHead.Length));
+            h.Overwrite(x, dStart);
+
+            // The field geometry: D's start block is shorter and ends inside one of C's lines, so the tail of that line
+            // sits between D's start block and C's remaining bytes.
+            Assert.True(dStart.Length < cStart.Length);
+            Assert.DoesNotContain(x + dStart.Length, EntryStarts(cStart, x));
+            h.Now = h.Now.AddMilliseconds(150);
+            await h.Pass();
+            Assert.True(h.Health.OverwriteRewinds >= 1);
+
+            // C ends: its end block lands at its own position, right behind its own (overwritten) start block.
+            Assert.Equal(x + cStart.Length, h.Length);
+            var cEnd = ExecutorEndBlock("12:00:07.0000000", 1, DetectionStdout);
+            h.Append(cEnd);
+            h.Now = h.Now.AddSeconds(6);
+            await h.Pass();
+
+            // IME's result for D reaches the tracker before D's own end block: the completion must wait for it.
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            Assert.Empty(h.Completed);
+
+            // D ends: its end block lands at ITS position, over the fragment and C's bytes; C's last line survives.
+            var dEnd = ExecutorEndBlock("12:00:09.5000000", 0, PlatformStdout);
+            Assert.True(dEnd.Length < cStart.Length - dStart.Length + cEnd.Length);
+            h.Overwrite(x + dStart.Length, dEnd);
+            h.Now = h.Now.AddMilliseconds(130);
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(RacePlatformId, script.PolicyId);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal(PlatformStdout.Replace("\r\n", "\n"), script.Stdout);
+            Assert.DoesNotContain(h.Completed, s => (s.Stdout ?? string.Empty).Contains("Detection"));
+
+            // The run is known to the registry reconciliation under the user id of its own lines (D-316).
+            Assert.Equal(RaceUserId, script.UserId);
+            Assert.False(string.IsNullOrEmpty(script.RunId));
+            h.Tracker.ScriptRuns.NotePassCompleted(DateTime.MaxValue.AddDays(-1));
+            Assert.Equal(PlatformRunClaim.Claimed, h.Tracker.ScriptRuns.TryClaim(RaceUserId, RacePlatformId, h.Now, out var run));
+            Assert.Equal(script.RunId, run!.RunId);
+        }
+
+        /// <summary>
+        /// The mirror image: a foreign executor whose stream position lies inside the platform start block (it opened
+        /// at the same end with a shorter start block) writes its end block there. Its first line merges with the head of
+        /// a platform line — cut inside the message or inside the trailer, which the parser would otherwise read up to
+        /// the foreign trailer — and its output line follows without any marker in between.
+        /// </summary>
+        [Theory]
+        [InlineData(15)]
+        [InlineData(-30)]
+        public async Task Foreign_end_block_merged_into_the_platform_start_block_never_reaches_the_platform_script(int cut)
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1548") + ExecutorEndBlock("12:00:00.5000000", 0, "detected"));
+            await h.Pass();
+            var x = h.Length;
+
+            var dStart = PlatformStartBlock("12:00:01.0000000", RacePlatformId, "2524");
+            h.Append(dStart);
+            await h.Pass();
+
+            // The foreign end block starts inside the line after D's argument line.
+            var lineAfterArgument = x + dStart.IndexOf("<![LOG[Powershell option gets invoked", StringComparison.Ordinal);
+            var lineLength = EntryAt("12:00:01.0000000", "Powershell option gets invoked").Length;
+            var at = lineAfterArgument + (cut > 0 ? cut : lineLength + cut);
+            var foreignEnd = ExecutorEndBlock("12:00:03.0000000", 1, "foreign output");
+            Assert.True(at + foreignEnd.Length < x + dStart.Length, "the foreign block must end inside D's start block");
+            h.Overwrite(at, foreignEnd);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            // No owner is provable behind the cut: the completion goes out without end-block data, never with the foreign one.
+            var script = Assert.Single(h.Completed);
+            Assert.Equal("Success", script.Result);
+            Assert.Null(script.ExitCode);
+            Assert.Null(script.Stdout);
+        }
+
+        [Fact]
+        public async Task Entry_read_unchanged_after_a_rewind_keeps_its_platform_marker()
+        {
+            const string platformId = "2b7d9e41-8c3a-4f60-a5d2-9e1b7c4f3a08";
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // Detection W waits for its script; detection X runs completely behind it; platform F starts behind X.
+            var wStart = DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1111");
+            var xRun = DetectionStartBlock("12:00:00.2000000", RaceDetectionAppId, "2222") + ExecutorEndBlock("12:00:00.4000000", 0, "x detected");
+            h.Append(wStart + xRun + PlatformStartBlock("12:00:01.0000000", platformId, "3333"));
+            await h.Pass();
+
+            // W ends at its own position, over the head of X's run; F's start block keeps its bytes and offset.
+            var wEnd = ExecutorEndBlock("12:00:02.0000000", 0, "w detected");
+            Assert.True(wEnd.Length < xRun.Length);
+            h.Overwrite(wStart.Length, wEnd);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+
+            // F's end block lands behind its start block: still F's, because F's marker survived with its bytes.
+            h.Append(ExecutorEndBlock("12:00:05.0000000", 7, "Hello from F"));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(platformId), sourceFileName: "IntuneManagementExtension.log");
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(platformId, script.PolicyId);
+            Assert.Equal(7, script.ExitCode);
+            Assert.Equal("Hello from F", script.Stdout);
+        }
+
+        [Fact]
+        public async Task Writer_boundary_read_unchanged_after_a_rewind_still_closes_the_platform_invocation()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // Detection Q waits for its script while detection R runs completely behind it.
+            var qStart = DetectionStartBlock("12:00:00.0000000", RaceFillerAppId, "1111");
+            var rRun = DetectionStartBlock("12:00:00.2000000", "6c3f8a20-1d5e-4b97-8f4a-0e2d6b9c7a13", "2222") + ExecutorEndBlock("12:00:00.4000000", 0, "r detected");
+            h.Append(qStart + rRun);
+            await h.Pass();
+            var x = h.Length;
+
+            // The race of the field case behind them: the boundary closes D.
+            var cStart = DetectionStartBlock("12:00:01.0000000", RaceDetectionAppId, "6416");
+            var dStart = PlatformStartBlock("12:00:01.2000000", RacePlatformId, "2524");
+            h.Append(cStart);
+            h.Overwrite(x, dStart);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            // Q ends at its own position, over R's run: the rewind starts in front of the race, whose bytes read unchanged.
+            var qEnd = ExecutorEndBlock("12:00:02.0000000", 0, "q detected");
+            Assert.True(qEnd.Length < rRun.Length);
+            h.Overwrite(qStart.Length, qEnd);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            // C's end block behind the boundary stays unowned; D's own end block completes D.
+            var cEnd = ExecutorEndBlock("12:00:07.0000000", 1, DetectionStdout);
+            h.Append(cEnd);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            Assert.Empty(h.Completed);
+
+            h.Overwrite(x + dStart.Length, ExecutorEndBlock("12:00:09.5000000", 0, PlatformStdout));
+            h.Now = h.Now.AddMilliseconds(130);
+            await h.Pass();
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal(PlatformStdout.Replace("\r\n", "\n"), script.Stdout);
+        }
+
+        [Fact]
+        public async Task Raw_text_in_the_executor_log_is_never_matched_and_closes_the_platform_invocation()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(PlatformStartBlock("12:00:00.0000000", RacePlatformId, "2524"));
+            await h.Pass();
+
+            // The tail of a cut line that happens to read like an exit line, then a foreign end block.
+            h.Append("Powershell exit code is 5\r\n" + ExecutorEndBlock("12:00:02.0000000", 6, "foreign output"));
+            // A fragment right at the bookmark stops the first pass for a check; the second one reads it.
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId), sourceFileName: "IntuneManagementExtension.log");
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Null(script.ExitCode);
+            Assert.Null(script.Stdout);
+        }
+
+        [Fact]
+        public async Task Fragment_in_the_ime_log_does_not_close_the_platform_run_context()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            // In the IME log the service writes the platform marker and the context line itself; the fragment in
+            // between is the tail of an executor's telemetry line and separates nothing.
+            h.Append(Entry(@"Script file C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\" + RaceUserId + "_" + RacePlatformId + ".ps1 is generated.", "17")
+                + "ing mananger...]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">\r\n"
+                + Entry("Launch powershell executor in user session", "17"));
+            await h.Pass();
+
+            h.Tracker.ProcessLogMessageForTest(PlatformResultLine(RacePlatformId));
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal("User", script.RunContext);
+        }
+
+        [Fact]
+        public async Task Cut_multi_line_output_adds_one_boundary_not_one_per_line()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(PlatformStartBlock("12:00:00.0000000", RacePlatformId, "2524"));
+            await h.Pass();
+            var markersBefore = h.Tracker.InvocationMarkerCountForTest("AgentExecutor.log");
+
+            var lines = string.Concat(Enumerable.Range(1, 600).Select(i => $"orphaned output line {i}\r\n"));
+            h.Append(lines);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            Assert.Equal(markersBefore + 1, h.Tracker.InvocationMarkerCountForTest("AgentExecutor.log"));
+        }
+
+        [Theory]
+        [InlineData("<![LOG[Powershell exit code is 0]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", true)]
+        [InlineData("<![LOG[write output done. output = line one\nline two, error = ]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", true)]
+        [InlineData("\uFEFF<![LOG[ExecutorLog AgentExecutor gets invoked]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", true)]
+        [InlineData("t code is 3]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        [InlineData("", false)]
+        [InlineData("<![LOG[Powe<![LOG[Powershell exit code is 1]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        [InlineData("<![LOG[Powershell option gets invoked]LOG]!><time=\"12:00:00.0000000\" da<![LOG[Powershell exit code is 1]LOG]!><time=\"12:00:01.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        [InlineData("<![LOG[write output done. output = line one\nline<![LOG[Agent executor completed.]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"AgentExecutor\" context=\"\" type=\"1\" thread=\"1\" file=\"\">", false)]
+        public void Single_cmtrace_record_is_told_apart_from_the_cut_of_two_writers(string text, bool expected)
+        {
+            Assert.Equal(expected, ImeLogTracker.IsSingleCmTraceRecord(text));
+        }
+
+        [Theory]
+        [InlineData("AgentExecutor.log", true)]
+        [InlineData("AgentExecutor-20261003-233348.log", true)]
+        [InlineData("IntuneManagementExtension.log", false)]
+        [InlineData("IntuneManagementExtension-20261003-233348.log", false)]
+        [InlineData("HealthScripts.log", false)]
+        [InlineData("AppWorkload.log", false)]
+        public void Writer_boundaries_apply_to_the_executor_log_live_and_rotated(string fileName, bool expected)
+        {
+            Assert.Equal(expected, ImeLogTracker.IsWriterBoundaryLogFile(fileName));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerOverwriteRewindTests.cs

@@ -0,0 +1,541 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Newtonsoft.Json;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// Session 46749560: IME's trace listener writes every log through one FileMode.Append
+    /// stream per process, so a process that resumes logging after another one appended
+    /// overwrites those bytes at its own stale position. The tracker had read the first version
+    /// and never saw the second — 6 of 16 script results and 4 of 16 executor end blocks were
+    /// lost while the final files looked intact. These tests drive that exact write pattern
+    /// (positional overwrite behind the bookmark) against the two multi-writer logs and pin the
+    /// contract: unchanged bytes never rewind, changed bytes are processed exactly once, and the
+    /// executor lines a rewind uncovers belong to the invocation that owns their file position.
+    /// </summary>
+    public sealed partial class ImeLogTrackerOverwriteRewindTests
+    {
+        private static readonly DateTime T0 = new DateTime(2026, 9, 10, 19, 30, 0, DateTimeKind.Utc);
+
+        private static List<ImeLogPattern> MarkerPatterns() => new List<ImeLogPattern>
+        {
+            new ImeLogPattern
+            {
+                PatternId = "T-MARK", Category = "always", Enabled = true,
+                Pattern = @"^marker (?<n>\d+)", Action = "noop",
+                Parameters = new Dictionary<string, string>(),
+            },
+        };
+
+        private static readonly string[] ScriptPatternIds =
+        {
+            "PS-AGENT-INVOCATION", "PS-AGENT-ARG", "PS-AGENT-SCRIPT-START", "PS-AGENT-EXITCODE",
+            "PS-AGENT-OUTPUT", "PS-AGENT-ERROR", "PS-AGENT-COMPLETED", "PS-SCRIPT-GENERATED", "PS-SCRIPT-CONTEXT", "PS-SCRIPT-RESULT",
+        };
+
+        /// <summary>The shipped pattern JSON — the same source combine.js embeds — so the contract is the real one.</summary>
+        private static List<ImeLogPattern> ScriptPatterns()
+        {
+            DirectoryInfo? dir = new DirectoryInfo(AppContext.BaseDirectory);
+            string? patternDir = null;
+            while (dir != null)
+            {
+                var candidate = Path.Combine(dir.FullName, "rules", "ime-log-patterns");
+                if (Directory.Exists(candidate)) { patternDir = candidate; break; }
+                dir = dir.Parent;
+            }
+            Assert.NotNull(patternDir);
+
+            var byId = new Dictionary<string, ImeLogPattern>(StringComparer.OrdinalIgnoreCase);
+            foreach (var file in Directory.GetFiles(patternDir, "*.json"))
+            {
+                var pattern = JsonConvert.DeserializeObject<ImeLogPattern>(File.ReadAllText(file));
+                if (pattern?.PatternId != null) byId[pattern.PatternId] = pattern;
+            }
+            return ScriptPatternIds.Select(id =>
+            {
+                Assert.True(byId.TryGetValue(id, out var p), $"Shipped IME pattern '{id}' not found under {patternDir}.");
+                return p!;
+            }).ToList();
+        }
+
+        private static string Entry(string message, string thread = "1")
+            => $"<![LOG[{message}]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"X\" context=\"\" type=\"1\" thread=\"{thread}\" file=\"\">\r\n";
+
+        private const string PlatformId = "d39eeef3-e88e-41a0-82d7-5e28ee7b5acf";
+        private const string PlatformStartLine =
+            @"Adding argument powershell with value C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\73d664e4-0886-4a73-b745-c694da45ddb4_d39eeef3-e88e-41a0-82d7-5e28ee7b5acf.ps1 to the named argument list.";
+        private const string DetectionStartLine =
+            @"Adding argument detectionScript with value C:\Windows\IMECache\DetectionScripts\App_cc46aa62-e93a-41a1-bdd0-44f57e92a66d.ps1 to the named argument list.";
+        private const string GeneratedLine =
+            @"Script file C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\73d664e4-0886-4a73-b745-c694da45ddb4_d39eeef3-e88e-41a0-82d7-5e28ee7b5acf.ps1 is generated.";
+        private const string ResultLine =
+            "[PowerShell] User Id = 73d664e4-0886-4a73-b745-c694da45ddb4, Policy id = " + PlatformId + ", policy result = Success";
+
+        private sealed class Harness : IDisposable
+        {
+            private readonly TempDirectory _tmp = new TempDirectory();
+            private readonly string _matchLog;
+            private readonly List<ImeLogPattern> _patterns;
+            public ImeLogTracker Tracker { get; private set; }
+            public DateTime Now { get; set; } = T0;
+            public string LogName { get; }
+            public string LogPath => Path.Combine(_tmp.Path, LogName);
+            public string StateDir { get; }
+            public List<ScriptExecutionState> Completed { get; } = new List<ScriptExecutionState>();
+
+            public Harness(string logName, List<ImeLogPattern> patterns)
+            {
+                LogName = logName;
+                _patterns = patterns;
+                var logDir = Path.Combine(_tmp.Path, "agent");
+                Directory.CreateDirectory(logDir);
+                _matchLog = Path.Combine(logDir, "ime-pattern-matches.log");
+                StateDir = Path.Combine(_tmp.Path, "state");
+                Tracker = Build();
+            }
+
+            private ImeLogTracker Build()
+            {
+                var t = new ImeLogTracker(_tmp.Path, _patterns, new AgentLogger(Path.Combine(_tmp.Path, "agent"), AgentLogLevel.Debug),
+                    matchLogPath: _matchLog, stateDirectory: StateDir);
+                t.UtcNowProvider = () => Now;
+                t.OnScriptCompleted = s => Completed.Add(s);
+                return t;
+            }
+
+            /// <summary>Agent restart: dispose, rebuild over the same state directory, restore the bookmark.</summary>
+            public void Restart()
+            {
+                Tracker.SaveStateForTest();
+                Tracker.Dispose();
+                Tracker = Build();
+                Tracker.LoadStateForTest();
+            }
+
+            public void Append(string text) => File.AppendAllText(LogPath, text, new UTF8Encoding(false));
+
+            /// <summary>What IME's stale writer does: write at its own position, over whatever is there.</summary>
+            public void Overwrite(long offset, string text)
+            {
+                using (var fs = new FileStream(LogPath, FileMode.Open, FileAccess.Write, FileShare.ReadWrite))
+                {
+                    fs.Seek(offset, SeekOrigin.Begin);
+                    var bytes = new UTF8Encoding(false).GetBytes(text);
+                    fs.Write(bytes, 0, bytes.Length);
+                }
+            }
+
+            public long Length => new FileInfo(LogPath).Length;
+
+            public Task Pass(CancellationToken token = default) => Tracker.CheckLogFilesAsync(token);
+
+            /// <summary>Marker numbers matched so far, in match order.</summary>
+            public List<int> Matched()
+            {
+                if (!File.Exists(_matchLog)) return new List<int>();
+                return File.ReadAllLines(_matchLog)
+                    .Select(l => Regex.Match(l, @"\[T-MARK\] <!\[LOG\[marker (\d+)"))
+                    .Where(m => m.Success).Select(m => int.Parse(m.Groups[1].Value)).ToList();
+            }
+
+            public ImeTrackerHealth Health => Tracker.GetHealthSnapshot();
+
+            public void Dispose()
+            {
+                Tracker.Dispose();
+                _tmp.Dispose();
+            }
+        }
+
+        // -----------------------------------------------------------------------
+        // Marker-level contract on AgentExecutor.log
+        // -----------------------------------------------------------------------
+
+        [Fact]
+        public async Task Unchanged_bytes_never_rewind_however_often_they_are_verified()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + "<![LOG[marker 2\nsecond line\n]LOG]!><time=\"12:00:00.0000000\" date=\"9-10-2026\" component=\"X\" context=\"\" type=\"1\" thread=\"1\" file=\"\">\r\n" + Entry("marker 3"));
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3 }, h.Matched());
+
+            for (var i = 0; i < 5; i++)
+            {
+                h.Tracker.RequestOverwriteCheckForTest();
+                h.Now = h.Now.AddSeconds(2);
+                await h.Pass();
+            }
+
+            Assert.Equal(new[] { 1, 2, 3 }, h.Matched());
+            Assert.Equal(0, h.Health.OverwriteRewinds);
+            Assert.Equal(5, h.Health.VerifyPasses);
+            Assert.Equal(3, h.Tracker.LedgerEntryCountForTest("AgentExecutor.log"));
+        }
+
+        [Fact]
+        public async Task Non_multi_writer_files_keep_no_ledger_and_are_never_verified()
+        {
+            using var h = new Harness("AppWorkload.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2"));
+            await h.Pass();
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddSeconds(2);
+            await h.Pass();
+
+            Assert.Equal(new[] { 1, 2 }, h.Matched());
+            Assert.Equal(0, h.Tracker.LedgerEntryCountForTest("AppWorkload.log"));
+            Assert.Equal(0, h.Health.VerifyPasses);
+            Assert.Equal(0, h.Health.VerifiedBytes);
+        }
+
+        [Fact]
+        public async Task Block_written_over_read_bytes_is_processed_once_and_the_surviving_tail_is_not_repeated()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            var one = Entry("marker 1");
+            h.Append(one + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3 }, h.Matched());
+
+            // A stale writer lays two entries over the first two (same length: marker 3 survives
+            // intact at its old offset). No growth, no fragment — only the end signal finds it.
+            h.Overwrite(0, Entry("marker 7") + Entry("marker 8"));
+            Assert.Equal(3 * one.Length, h.Length);
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            Assert.Equal(new[] { 1, 2, 3, 7, 8 }, h.Matched());
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+            Assert.Equal(3 * one.Length, h.Health.OverwriteBytesReprocessed);
+            Assert.Equal(3, h.Tracker.LedgerEntryCountForTest("AgentExecutor.log"));
+
+            // Nothing left to find.
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddSeconds(2);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3, 7, 8 }, h.Matched());
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+        }
+
+        [Fact]
+        public async Task Block_that_cuts_an_old_entry_leaves_a_fragment_that_is_never_matched()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+
+            // Longer than two old entries, shorter than three: the tail of marker 3's line survives
+            // as a fragment behind the new block.
+            h.Overwrite(0, Entry("marker 7") + Entry("marker 8 is a little longer"));
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            Assert.Equal(new[] { 1, 2, 3, 7, 8 }, h.Matched());
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+        }
+
+        [Fact]
+        public async Task Guard_zone_catches_a_short_block_when_the_file_grows_without_any_signal()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+
+            // Same-length replacement of marker 1 (no fragment), then an ordinary append by
+            // another writer: the growth pass re-checks the last 4 KB and finds the change.
+            h.Overwrite(0, Entry("marker 7"));
+            h.Append(Entry("marker 4"));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            Assert.Equal(new[] { 1, 2, 3, 7, 4 }, h.Matched());
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+            Assert.Equal(1, h.Health.VerifyPasses); // the full check that follows a guard hit
+            Assert.True(h.Health.VerifiedBytes > 0);
+        }
+
+        [Fact]
+        public async Task Guard_hit_rewinds_to_the_true_start_of_the_block_not_the_guard_zone()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            // ~6 KB of entries so the guard zone covers only the last few.
+            var sb = new StringBuilder();
+            for (var i = 1; i <= 60; i++) sb.Append(Entry($"marker {i}"));
+            h.Append(sb.ToString());
+            await h.Pass();
+            Assert.Equal(60, h.Matched().Count);
+
+            // A block over everything plus one more entry: the guard sees a change at its
+            // zone start, the full check must place the rewind at offset 0.
+            var block = new StringBuilder();
+            for (var i = 101; i <= 161; i++) block.Append(Entry($"marker {i}"));
+            h.Overwrite(0, block.ToString());
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            var matched = h.Matched();
+            Assert.Equal(60 + 61, matched.Count);
+            Assert.Equal(Enumerable.Range(101, 61), matched.Skip(60));
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+        }
+
+        [Fact]
+        public async Task Fragment_at_the_bookmark_triggers_the_check_when_no_ledger_entry_starts_in_the_guard_zone()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            var one = Entry("marker 1");
+            var big = Entry("marker 2 " + new string('x', 6000));
+            h.Append(one + big);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2 }, h.Matched());
+
+            // The 6 KB entry is the last ledger entry and starts before the 4 KB guard zone, so
+            // the guard has nothing to check. The stale writer's block is longer than that entry:
+            // the pass after it starts mid-line — a fragment — and must not match it raw.
+            h.Overwrite(one.Length, Entry("marker 7 " + new string('y', 3000)) + Entry("marker 8 " + new string('z', 3100)));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2 }, h.Matched());
+
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 7, 8 }, h.Matched());
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+        }
+
+        [Fact]
+        public async Task Hidden_block_is_found_by_the_cadence_while_a_script_is_in_flight_and_the_cadence_is_throttled()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+
+            // A platform script is pending → contention. First pass in contention verifies at once.
+            h.Tracker.SeedPendingPlatformScriptForTesting("policyX", exitCode: null, exitObservedAtUtc: null, startedAtUtc: T0);
+            h.Now = T0.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(1, h.Health.VerifyPasses);
+
+            // Same-length replacement, no growth, no signal: only the cadence can find it —
+            // and not before a second has passed since the last verification.
+            h.Overwrite(0, Entry("marker 7"));
+            h.Now = T0.AddMilliseconds(500);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3 }, h.Matched());
+            Assert.Equal(1, h.Health.VerifyPasses);
+
+            h.Now = T0.AddMilliseconds(1200);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3, 7 }, h.Matched());
+            Assert.Equal(2, h.Health.VerifyPasses);
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+        }
+
+        [Fact]
+        public async Task Without_contention_or_signal_nothing_is_verified()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2"));
+            await h.Pass();
+
+            for (var i = 0; i < 20; i++)
+            {
+                h.Now = h.Now.AddSeconds(1);
+                await h.Pass();
+            }
+
+            Assert.Equal(0, h.Health.VerifyPasses);
+            Assert.Equal(0, h.Health.VerifiedBytes);
+        }
+
+        [Fact]
+        public async Task Restart_seeds_the_ledger_so_an_overwrite_after_the_restart_is_still_found()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+            h.Restart();
+            Assert.Equal(0, h.Tracker.LedgerEntryCountForTest("AgentExecutor.log"));
+
+            // First pass after the restart: nothing new to read, but the ledger is seeded from
+            // the bytes behind the persisted bookmark.
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(3, h.Tracker.LedgerEntryCountForTest("AgentExecutor.log"));
+
+            h.Overwrite(0, Entry("marker 7"));
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            Assert.Equal(new[] { 1, 2, 3, 7 }, h.Matched());
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+
+            // The counter is part of the persisted health.
+            h.Restart();
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+        }
+
+        [Fact]
+        public async Task Rollover_clears_the_ledger_and_the_new_file_is_read_without_a_false_rewind()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+
+            File.WriteAllText(h.LogPath, Entry("marker 7") + Entry("marker 8"), new UTF8Encoding(false));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3, 7, 8 }, h.Matched());
+
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddSeconds(2);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3, 7, 8 }, h.Matched());
+            Assert.Equal(0, h.Health.OverwriteRewinds);
+            Assert.Equal(2, h.Tracker.LedgerEntryCountForTest("AgentExecutor.log"));
+        }
+
+        [Fact]
+        public async Task Cancelled_pass_does_not_lose_a_pending_check()
+        {
+            using var h = new Harness("AgentExecutor.log", MarkerPatterns());
+            h.Append(Entry("marker 1") + Entry("marker 2") + Entry("marker 3"));
+            await h.Pass();
+            h.Overwrite(0, Entry("marker 7") + Entry("marker 8"));
+            h.Tracker.RequestOverwriteCheckForTest();
+            h.Now = h.Now.AddMilliseconds(100);
+
+            using (var cts = new CancellationTokenSource())
+            {
+                cts.Cancel();
+                await h.Pass(cts.Token);
+            }
+
+            // The cancelled pass touched nothing after the rewind; the next one reads it all.
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(new[] { 1, 2, 3, 7, 8 }, h.Matched());
+        }
+
+        // -----------------------------------------------------------------------
+        // The field scenario with the shipped patterns
+        // -----------------------------------------------------------------------
+
+        [Fact]
+        public async Task Executor_end_block_written_over_a_detection_invocation_belongs_to_its_own_script()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+
+            // Executor E starts its platform script and waits for PowerShell.
+            h.Append(Entry("ExecutorLog AgentExecutor gets invoked") + Entry(PlatformStartLine) + Entry("[Executor] created powershell with process id 12708"));
+            await h.Pass();
+            var executorPosition = h.Length;
+
+            // Detection executor D appends its whole run while E waits — the tracker reads it.
+            var detectionBlock = Entry("ExecutorLog AgentExecutor gets invoked") + Entry(DetectionStartLine)
+                + Entry("Powershell exit code is 3") + Entry("write output done. output = detected nothing, error = ")
+                + Entry("Agent executor completed.") + Entry(@"Writing result: False to resultFilePath: C:\x\App_cc46aa62.txt");
+            h.Append(detectionBlock);
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            // E ends: its end block lands at its own stale position, over D's lines.
+            var endBlock = Entry("Powershell exit code is 0") + Entry("write output done. output = Hello from E, error = ") + Entry("Agent executor completed.");
+            Assert.True(endBlock.Length < detectionBlock.Length);
+            h.Overwrite(executorPosition, endBlock);
+
+            // Nothing visible signalled the end; the cadence (E is pending) finds the block.
+            h.Now = h.Now.AddSeconds(1.5);
+            await h.Pass();
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+
+            // IME's result line (in the other file) completes the script with E's own data.
+            h.Tracker.ProcessLogMessageForTest(ResultLine);
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(PlatformId, script.PolicyId);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal("ime_policy_result", script.ResultSource);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal("Hello from E", script.Stdout);
+        }
+
+        [Fact]
+        public async Task Detection_exit_lines_read_before_the_overwrite_never_reach_the_platform_script()
+        {
+            using var h = new Harness("AgentExecutor.log", ScriptPatterns());
+            h.Append(Entry("ExecutorLog AgentExecutor gets invoked") + Entry(PlatformStartLine) + Entry("[Executor] created powershell with process id 1"));
+            await h.Pass();
+            h.Append(Entry("ExecutorLog AgentExecutor gets invoked") + Entry(DetectionStartLine)
+                + Entry("Powershell exit code is 3") + Entry("write output done. output = detected nothing, error = ") + Entry("Agent executor completed."));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+
+            // The platform result arrives without any end block ever becoming visible: held for
+            // the grace, then emitted — the detection's exit code 3 must not stand in.
+            h.Tracker.ProcessLogMessageForTest(ResultLine);
+            Assert.Empty(h.Completed);
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+            var script = Assert.Single(h.Completed);
+            Assert.Equal("Success", script.Result);
+            Assert.Null(script.ExitCode);
+            Assert.Null(script.Stdout);
+        }
+
+        [Fact]
+        public async Task Ime_result_line_hidden_by_an_executor_start_line_is_recovered_from_the_ime_log()
+        {
+            using var h = new Harness("IntuneManagementExtension.log", ScriptPatterns());
+            // Seen empty first: the start lines are fresh and anchor themselves like the recovered result line will,
+            // so start and result sit on one timeline whatever the host's own zone is.
+            h.Append(string.Empty);
+            await h.Pass();
+            h.Append(Entry(GeneratedLine, "17") + Entry("Launch powershell executor in user session", "17") + Entry("process id = 10608", "17"));
+            await h.Pass();
+            var servicePosition = h.Length;
+
+            // The executor process appends its telemetry start line at the true end of file.
+            h.Append(Entry("[Telemetry] Telemetry is enabled. Starting mananger...", "1"));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Empty(h.Completed);
+
+            // The service's first write after the script wait lands at ITS position — over the
+            // executor's line; the block is longer, so the pass sees a fragment at the bookmark.
+            h.Overwrite(servicePosition, Entry("Execution is done, collecting result", "17") + Entry(ResultLine, "17") + Entry("[PowerShell] Success, Result details length: 315", "17"));
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            h.Now = h.Now.AddMilliseconds(100);
+            await h.Pass();
+            Assert.Equal(1, h.Health.OverwriteRewinds);
+
+            // Recovered on the IME side alone (this harness has no AgentExecutor.log): held for
+            // the end block, emitted without an exit code after the grace.
+            Assert.Empty(h.Completed);
+            h.Now = h.Now.Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Tracker.FlushPendingPlatformScriptResults(h.Now);
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(PlatformId, script.PolicyId);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal("ime_policy_result", script.ResultSource);
+            Assert.Equal("User", script.RunContext);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerPlatformScriptContaminationTests.cs

@@ -36,8 +36,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
         // silently passing against a stale inline copy.
         private static readonly string[] RequiredPatternIds =
         {
-            "PS-AGENT-INVOCATION", "PS-AGENT-SCRIPT-START", "PS-AGENT-EXITCODE",
-            "PS-AGENT-OUTPUT", "PS-SCRIPT-RESULT",
+            "PS-AGENT-INVOCATION", "PS-AGENT-ARG", "PS-AGENT-SCRIPT-START", "PS-AGENT-EXITCODE",
+            "PS-AGENT-OUTPUT", "PS-AGENT-COMPLETED", "PS-SCRIPT-GENERATED", "PS-SCRIPT-CONTEXT",
+            "PS-SCRIPT-RESULT", "HS-INVOCATION",
         };
 
         private static List<ImeLogPattern> ScriptPatterns()
@@ -83,6 +84,24 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
         private const string RemediationStartLine =
             @"Adding argument remediationScript with value C:\Windows\IMECache\HealthScripts\446f0450-d0ee-404c-8dc0-a74123bde31f_1\detect.ps1 to the named argument list.";
 
+        private const string ImeLog = "IntuneManagementExtension.log";
+        private const string HealthLog = "HealthScripts.log";
+        private const string ExecutorLog = "AgentExecutor.log";
+
+        private const string PlatformGeneratedLine =
+            @"Script file C:\Program Files (x86)\Microsoft Intune Management Extension\Policies\Scripts\00000000-0000-0000-0000-000000000000_c3e0124c-4936-4bfd-afcc-c7fe1d84d104.ps1 is generated";
+
+        private static readonly string PlatformResultLine =
+            $"[PowerShell] User Id = 00000000-0000-0000-0000-000000000000, Policy id = {PlatformId}, policy result = Success";
+
+        // The health-script worker (IME AgentCommon ScriptWorker) writes its command line, the launch
+        // line and the exit line to IntuneManagementExtension.log AND HealthScripts.log — session
+        // 24dc69d1 (IME 1.105.152.0), where the exit line pre-filled a pending platform script's exit
+        // code and the launch line its context.
+        private const string HealthScriptCommandLine =
+            @"""C:\Program Files (x86)\Microsoft Intune Management Extension\agentexecutor.exe""  -remediationScript  """"C:\WINDOWS\IMECache\HealthScripts\446f0450-d0ee-404c-8dc0-a74123bde31f_1\detect.ps1"""" ""C:\WINDOWS\IMECache\HealthScripts\446f0450-d0ee-404c-8dc0-a74123bde31f_1\detect.ps1.result"" 60";
+        private const string HealthScriptExitLine = "Powershell execution is done, exitCode = 5";
+
         private static ImeLogTracker BuildTracker(TempDirectory tmp, out List<ScriptExecutionState> emitted)
         {
             var captured = new List<ScriptExecutionState>();
@@ -111,9 +130,13 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             tracker.ProcessLogMessageForTest("Powershell exit code is 0");
             tracker.ProcessLogMessageForTest("write output done. output = [Compliant] No Classic Teams found, error = ");
 
-            // Authoritative IME result for the PLATFORM script (keyed by policyId).
+            // Authoritative IME result for the PLATFORM script (keyed by policyId). Its own end
+            // block never comes here, so the result is held until the shutdown flush — which must
+            // not pick up the remediation's exit/output either.
             tracker.ProcessLogMessageForTest(
                 $"[PowerShell] User Id = 00000000-0000-0000-0000-000000000000, Policy id = {PlatformId}, policy result = Failed");
+            Assert.Empty(emitted);
+            tracker.FlushPendingPlatformScriptResults(System.DateTime.UtcNow, force: true);
 
             var script = Assert.Single(emitted);
             Assert.Equal(PlatformId, script.PolicyId);
@@ -145,5 +168,100 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.Equal(0, script.ExitCode);
             Assert.Equal("Hello from c3e0124c", script.Stdout);
         }
+
+        // -----------------------------------------------------------------------
+        // Health-script lines never feed a platform slot (session 24dc69d1)
+        // -----------------------------------------------------------------------
+
+        [Fact]
+        public void No_shipped_pattern_reads_the_health_script_workers_exit_line()
+        {
+            // "Powershell execution is done, exitCode = N" is the health-script worker's line only;
+            // as PS-SCRIPT-EXITCODE (no scriptType) it pre-filled the exit code of whichever platform
+            // script was pending, which then emitted without waiting for its own end block.
+            foreach (var file in Directory.GetFiles(FindRulesPatternDir(), "*.json"))
+            {
+                var pattern = JsonConvert.DeserializeObject<ImeLogPattern>(File.ReadAllText(file))!;
+                Assert.False(System.Text.RegularExpressions.Regex.IsMatch(HealthScriptExitLine, pattern.Pattern),
+                    $"{pattern.PatternId} matches the health-script worker's exit line");
+            }
+        }
+
+        [Fact]
+        public void Health_script_exit_line_in_the_ime_log_never_pre_fills_the_platform_slot()
+        {
+            using var tmp = new TempDirectory();
+            var tracker = BuildTracker(tmp, out var emitted);
+
+            tracker.ProcessLogMessageForTest(PlatformGeneratedLine, sourceFileName: ImeLog);
+            // A health script that ran in parallel finishes: its exit line lands inside the platform
+            // run's window (c81b8053 had "exit code 0" before its executor even started).
+            tracker.ProcessLogMessageForTest(HealthScriptExitLine, sourceFileName: ImeLog);
+            tracker.ProcessLogMessageForTest(PlatformResultLine, sourceFileName: ImeLog);
+
+            // No exit code of its own → held for the end block, never emitted with the health script's 5.
+            Assert.Empty(emitted);
+            tracker.FlushPendingPlatformScriptResults(DateTime.UtcNow, force: true);
+            var script = Assert.Single(emitted);
+            Assert.Null(script.ExitCode);
+            Assert.Equal("Success", script.Result);
+        }
+
+        [Fact]
+        public void Health_script_launch_line_in_the_ime_log_does_not_flip_the_platform_context()
+        {
+            using var tmp = new TempDirectory();
+            var tracker = BuildTracker(tmp, out var emitted);
+
+            tracker.ProcessLogMessageForTest(PlatformGeneratedLine, sourceFileName: ImeLog);
+            tracker.ProcessLogMessageForTest("Launch powershell executor in user session", sourceFileName: ImeLog);
+            // The health-script worker launches its executor while the platform script runs: its
+            // command line opens an invocation that owns nothing, so its launch line stays there.
+            tracker.ProcessLogMessageForTest(HealthScriptCommandLine, sourceFileName: ImeLog);
+            tracker.ProcessLogMessageForTest("Launch powershell executor in machine session", sourceFileName: ImeLog);
+            tracker.ProcessLogMessageForTest(PlatformResultLine, sourceFileName: ImeLog);
+            tracker.FlushPendingPlatformScriptResults(DateTime.UtcNow, force: true);
+
+            var script = Assert.Single(emitted);
+            Assert.Equal("User", script.RunContext);
+        }
+
+        [Fact]
+        public void Lines_from_the_health_scripts_log_never_resolve_to_a_platform_script()
+        {
+            using var tmp = new TempDirectory();
+            var tracker = BuildTracker(tmp, out var emitted);
+
+            tracker.ProcessLogMessageForTest("ExecutorLog AgentExecutor gets invoked", sourceFileName: ExecutorLog);
+            tracker.ProcessLogMessageForTest(PlatformStartLine, sourceFileName: ExecutorLog);
+            // HealthScripts.log never carries a platform marker — the run in flight is not the
+            // fallback owner of the lines there.
+            tracker.ProcessLogMessageForTest("Launch powershell executor in machine session", sourceFileName: HealthLog);
+            tracker.ProcessLogMessageForTest(PlatformResultLine, sourceFileName: ImeLog);
+            tracker.FlushPendingPlatformScriptResults(DateTime.UtcNow, force: true);
+
+            var script = Assert.Single(emitted);
+            Assert.Null(script.RunContext);
+        }
+
+        [Fact]
+        public void Context_line_after_an_ime_log_rollover_still_finds_the_run_in_flight()
+        {
+            using var tmp = new TempDirectory();
+            var tracker = BuildTracker(tmp, out var emitted);
+
+            tracker.ProcessLogMessageForTest(PlatformGeneratedLine, sourceFileName: ImeLog);
+            tracker.ProcessLogMessageForTest("ExecutorLog AgentExecutor gets invoked", sourceFileName: ExecutorLog);
+            tracker.ProcessLogMessageForTest(PlatformStartLine, sourceFileName: ExecutorLog);
+            // IME rolls the log over between its two lines: the fresh file has no markers, but
+            // platform runs open there — the run in flight still owns the context line.
+            tracker.ClearInvocationMarkersForTest(ImeLog);
+            tracker.ProcessLogMessageForTest("Launch powershell executor in user session", sourceFileName: ImeLog);
+            tracker.ProcessLogMessageForTest(PlatformResultLine, sourceFileName: ImeLog);
+            tracker.FlushPendingPlatformScriptResults(DateTime.UtcNow, force: true);
+
+            var script = Assert.Single(emitted);
+            Assert.Equal("User", script.RunContext);
+        }
     }
 }

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerPlatformScriptFallbackTests.cs

@@ -39,7 +39,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             tracker.SeedPendingPlatformScriptForTesting("dece354a", exitCode: 0, exitObservedAtUtc: observedAt, stdout: "Script start.\nScript end.");
 
             // Well past the grace window — should emit.
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
 
             var script = Assert.Single(emitted);
             Assert.Equal("dece354a", script.PolicyId);
@@ -60,11 +60,11 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             tracker.SeedPendingPlatformScriptForTesting("60b43a2e", exitCode: 0, exitObservedAtUtc: observedAt);
 
             // Inside the grace window — IME might still log its result; do not emit yet.
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(5));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(5));
             Assert.Empty(emitted);
 
             // Past the grace window — emit.
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
             Assert.Single(emitted);
         }
 
@@ -78,13 +78,38 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             tracker.SeedPendingPlatformScriptForTesting("846cea22", exitCode: 0, exitObservedAtUtc: observedAt);
 
             // Shutdown flush right after exit — grace not elapsed, but force emits anyway.
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(1), force: true);
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(1), force: true);
 
             Assert.Single(emitted);
         }
 
+        [Theory]
+        // IME's verdict is Success exactly when the error file is empty, whatever the exit code. Judged by the exit
+        // code, session 67ae751c showed exit 0 with the script's own stderr as Success, and 46a41a0a an exit 1 without
+        // stderr as Failed, a run IME reported as Success one cycle earlier.
+        [InlineData(0, "Invoke-WebRequest : The remote name could not be resolved", "Failed")]
+        [InlineData(1, "", "Success")]
+        [InlineData(1, "  \n", "Success")]
+        [InlineData(0, "", "Success")]
+        [InlineData(1, null, "Failed")]
+        [InlineData(0, null, "Success")]
+        public void Fallback_judges_like_ime_by_the_stderr_it_read(int exitCode, string? stderr, string expected)
+        {
+            using var tmp = new TempDirectory();
+            var tracker = BuildTracker(tmp, out var emitted);
+            var observedAt = new DateTime(2026, 6, 19, 12, 59, 4, DateTimeKind.Utc);
+
+            tracker.SeedPendingPlatformScriptForTesting("0d2294bf", exitCode: exitCode, exitObservedAtUtc: observedAt, stderr: stderr);
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
+
+            var script = Assert.Single(emitted);
+            Assert.Equal(expected, script.Result);
+            Assert.Equal(exitCode, script.ExitCode);
+            Assert.Equal("agentexecutor_fallback", script.ResultSource);
+        }
+
         [Fact]
-        public void Nonzero_exit_code_emits_failed_result()
+        public void Nonzero_exit_code_without_a_stderr_line_emits_failed_result()
         {
             using var tmp = new TempDirectory();
             var tracker = BuildTracker(tmp, out var emitted);
@@ -92,7 +117,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
 
             tracker.SeedPendingPlatformScriptForTesting("bad5c0de", exitCode: 1, exitObservedAtUtc: observedAt);
 
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
 
             var script = Assert.Single(emitted);
             Assert.Equal(1, script.ExitCode);
@@ -109,7 +134,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             // Started but no exit code yet → still running, must not be emitted even on force flush.
             tracker.SeedPendingPlatformScriptForTesting("running", exitCode: null, exitObservedAtUtc: null);
 
-            tracker.FlushStalePlatformScriptResults(DateTime.UtcNow, force: true);
+            tracker.FlushPendingPlatformScriptResults(DateTime.UtcNow, force: true);
 
             Assert.Empty(emitted);
         }
@@ -122,7 +147,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             var observedAt = new DateTime(2026, 6, 19, 12, 59, 4, DateTimeKind.Utc);
 
             tracker.SeedPendingPlatformScriptForTesting("dece354a", exitCode: 0, exitObservedAtUtc: observedAt);
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
             Assert.Single(emitted);
 
             // IME finally logs its PS-SCRIPT-RESULT line — must NOT produce a second event.
@@ -138,7 +163,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             var observedAt = new DateTime(2026, 6, 19, 12, 59, 4, DateTimeKind.Utc);
 
             tracker.SeedPendingPlatformScriptForTesting("dece354a", exitCode: 0, exitObservedAtUtc: observedAt);
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
 
             // The exit-observed timestamp must travel on the emitted state so the adapter can bind
             // the event to it instead of an unrelated "last matched" line parsed during the grace.
@@ -156,14 +181,14 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
 
             // Run 1 of policy X — fallback emits.
             tracker.SeedPendingPlatformScriptForTesting("policyX", exitCode: 0, exitObservedAtUtc: firstRun);
-            tracker.FlushStalePlatformScriptResults(firstRun.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(firstRun.AddSeconds(20));
             Assert.Single(emitted);
 
             // Run 2 of the SAME policy later in the same agent lifetime (IME re-evaluation / retry)
             // must NOT be deduped away — the fresh start clears the prior emitted-marker.
             var secondRun = firstRun.AddMinutes(30);
             tracker.SeedPendingPlatformScriptForTesting("policyX", exitCode: 0, exitObservedAtUtc: secondRun);
-            tracker.FlushStalePlatformScriptResults(secondRun.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(secondRun.AddSeconds(20));
             Assert.Equal(2, emitted.Count);
         }
 
@@ -182,7 +207,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.Equal("ime_policy_result", script.ResultSource);
 
             // Later fallback pass must find nothing pending → no duplicate.
-            tracker.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
             Assert.Single(emitted);
         }
     }

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerPollTimingTests.cs

@@ -0,0 +1,95 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// The poll loop's timing maxima (session c3ecb568: the loop was not scheduled for 26 s at
+    /// 100 % VM CPU and nothing in the telemetry could show it): the longest pass and the
+    /// longest pause between two passes, on a monotonic clock, restart-safe like the other
+    /// health counters.
+    /// </summary>
+    public sealed class ImeLogTrackerPollTimingTests
+    {
+        /// <summary>Monotonic readings the tracker takes at the start and the end of every pass.</summary>
+        private sealed class Clock
+        {
+            private readonly Queue<long> _readings = new Queue<long>();
+            public void Enqueue(params long[] ms) { foreach (var m in ms) _readings.Enqueue(m); }
+            public long Next() => _readings.Dequeue();
+        }
+
+        private static ImeLogTracker Build(TempDirectory tmp, Clock clock)
+        {
+            var tracker = new ImeLogTracker(tmp.Path, new List<ImeLogPattern>(), new AgentLogger(tmp.Path, AgentLogLevel.Info), stateDirectory: tmp.Path);
+            tracker.MonotonicMillisProvider = clock.Next;
+            return tracker;
+        }
+
+        [Fact]
+        public async Task Longest_pass_and_longest_pause_are_kept_as_session_maxima()
+        {
+            using var tmp = new TempDirectory();
+            var clock = new Clock();
+            var tracker = Build(tmp, clock);
+
+            // Pass 1 takes 30 ms; the loop is not scheduled again for 26.1 s; pass 2 takes 10 ms,
+            // pass 3 follows after the normal 100 ms.
+            clock.Enqueue(0, 30, 26130, 26140, 26240, 26245);
+            await tracker.RunPollPassAsync(CancellationToken.None);
+            await tracker.RunPollPassAsync(CancellationToken.None);
+            await tracker.RunPollPassAsync(CancellationToken.None);
+
+            var health = tracker.GetHealthSnapshot();
+            Assert.Equal(30, health.PassMaxMs);
+            Assert.Equal(26100, health.PassGapMaxMs);
+            tracker.Dispose();
+        }
+
+        [Fact]
+        public void A_fresh_tracker_reports_zero()
+        {
+            using var tmp = new TempDirectory();
+            var tracker = Build(tmp, new Clock());
+
+            var health = tracker.GetHealthSnapshot();
+            Assert.Equal(0, health.PassMaxMs);
+            Assert.Equal(0, health.PassGapMaxMs);
+            tracker.Dispose();
+        }
+
+        [Fact]
+        public async Task Maxima_survive_a_restart_and_are_never_lowered()
+        {
+            using var tmp = new TempDirectory();
+            var clock = new Clock();
+            var tracker1 = Build(tmp, clock);
+            clock.Enqueue(0, 40, 5140, 5150);
+            await tracker1.RunPollPassAsync(CancellationToken.None);
+            await tracker1.RunPollPassAsync(CancellationToken.None);
+            tracker1.SaveStateForTest();
+            tracker1.Dispose();
+
+            var tracker2 = Build(tmp, clock);
+            tracker2.LoadStateForTest();
+            Assert.Equal(40, tracker2.GetHealthSnapshot().PassMaxMs);
+            Assert.Equal(5100, tracker2.GetHealthSnapshot().PassGapMaxMs);
+
+            // The first pass after a restart has no pause to measure; a calmer session afterwards
+            // never lowers what the session already saw.
+            clock.Enqueue(6000, 6010, 6110, 6115);
+            await tracker2.RunPollPassAsync(CancellationToken.None);
+            await tracker2.RunPollPassAsync(CancellationToken.None);
+            var health = tracker2.GetHealthSnapshot();
+            Assert.Equal(40, health.PassMaxMs);
+            Assert.Equal(5100, health.PassGapMaxMs);
+            tracker2.Dispose();
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerResultHoldTests.cs

@@ -0,0 +1,332 @@
+using System;
+using System.Collections.Generic;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// The IME result waits for its executor end block (session e7f3c910): PS-SCRIPT-RESULT can
+    /// reach the tracker before the AgentExecutor.log end block of the same run — an overwritten
+    /// block is recovered one pass after the result that triggers the ledger check, the
+    /// AgentExecutor.log read of a pass may precede the exit line by milliseconds, or the poll
+    /// loop stalled. Emitting at once lost the exit code and, when the late start line reopened
+    /// the slot, produced a fallback duplicate 15 s later.
+    /// </summary>
+    public sealed class ImeLogTrackerResultHoldTests
+    {
+        private static readonly DateTime T0 = new DateTime(2026, 9, 10, 22, 13, 35, DateTimeKind.Utc);
+
+        private sealed class Harness : IDisposable
+        {
+            private readonly TempDirectory _tmp = new TempDirectory();
+            public ImeLogTracker Tracker { get; private set; }
+            public DateTime Now { get; set; } = T0;
+            public List<ScriptExecutionState> Completed { get; } = new List<ScriptExecutionState>();
+            public List<ScriptStartedInfo> Started { get; } = new List<ScriptStartedInfo>();
+
+            public Harness() { Tracker = Build(); }
+
+            private ImeLogTracker Build()
+            {
+                var t = new ImeLogTracker(_tmp.Path, new List<ImeLogPattern>(), new AgentLogger(_tmp.Path, AgentLogLevel.Info), stateDirectory: _tmp.Path);
+                t.UtcNowProvider = () => Now;
+                t.OnScriptCompleted = s => Completed.Add(s);
+                t.OnScriptStarted = s => Started.Add(s);
+                return t;
+            }
+
+            /// <summary>Agent restart over the same state directory.</summary>
+            public void Restart()
+            {
+                Tracker.SaveStateForTest();
+                Tracker.Dispose();
+                Tracker = Build();
+                Tracker.LoadStateForTest();
+            }
+
+            /// <summary>A start line (IME "Script file … is generated" or the executor's argument line) with its source timestamp.</summary>
+            public void Start(string id, DateTime lineTs)
+            {
+                Tracker.LastMatchedLogTimestamp = lineTs;
+                Tracker.NextTestEntry();
+                Tracker.HandlePlatformScriptStarted(id);
+            }
+
+            public void Result(string id, DateTime lineTs, string result = "Success")
+                => Tracker.CompletePlatformScriptFromImeResultForTesting(id, result, lineTs);
+
+            public void Exit(string id, DateTime lineTs, int exitCode = 0)
+                => Tracker.RecordPlatformScriptExitCodeForTesting(id, exitCode, lineTs);
+
+            /// <summary>The end-of-pass flush at the harness clock.</summary>
+            public void Flush(bool force = false) => Tracker.FlushPendingPlatformScriptResults(Now, force);
+
+            public void Dispose()
+            {
+                Tracker.Dispose();
+                _tmp.Dispose();
+            }
+        }
+
+        [Fact]
+        public void Result_before_the_end_block_is_held_and_emits_once_with_the_exit_code()
+        {
+            using var h = new Harness();
+            h.Start("376ee51a", T0);
+            h.Now = T0.AddSeconds(2);
+            h.Result("376ee51a", T0.AddSeconds(2));
+            Assert.Empty(h.Completed);
+            h.Now = T0.AddSeconds(2.1);
+            h.Flush();
+            Assert.Empty(h.Completed);
+
+            // The end block surfaces on the next pass (ledger rewind or plain read lag).
+            h.Exit("376ee51a", T0.AddSeconds(1.99));
+            h.Now = T0.AddSeconds(2.2);
+            h.Flush();
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal("ime_policy_result", script.ResultSource);
+            Assert.Equal(T0.AddSeconds(2), script.ResultObservedAtUtc);
+            Assert.Equal("PS-SCRIPT-RESULT", script.ResultPatternId);
+            Assert.Equal(T0, script.StartedAtUtc);
+
+            // Nothing fires twice: later passes, a repeated result line, the 15 s fallback window.
+            h.Now = T0.AddSeconds(30);
+            h.Flush();
+            h.Result("376ee51a", T0.AddSeconds(2));
+            Assert.Single(h.Completed);
+        }
+
+        [Fact]
+        public void Result_with_the_end_block_already_read_emits_at_once()
+        {
+            using var h = new Harness();
+            h.Start("847da54e", T0);
+            h.Exit("847da54e", T0.AddSeconds(2.3));
+            h.Now = T0.AddSeconds(2.31);
+            h.Result("847da54e", T0.AddSeconds(2.31));
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Null(script.ResultHeldSinceUtc);
+            Assert.Equal(T0.AddSeconds(2.31), script.ResultObservedAtUtc);
+        }
+
+        [Fact]
+        public void Held_result_emits_without_exit_code_after_the_grace()
+        {
+            using var h = new Harness();
+            h.Start("784fcaf5", T0);
+            h.Now = T0.AddSeconds(2);
+            h.Result("784fcaf5", T0.AddSeconds(2));
+
+            h.Now = T0.AddSeconds(2).Add(ImeLogTracker.PlatformScriptEndBlockGrace).AddMilliseconds(-100);
+            h.Flush();
+            Assert.Empty(h.Completed);
+
+            h.Now = T0.AddSeconds(2).Add(ImeLogTracker.PlatformScriptEndBlockGrace);
+            h.Flush();
+            var script = Assert.Single(h.Completed);
+            Assert.Null(script.ExitCode);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal("ime_policy_result", script.ResultSource);
+
+            // An exit line surfacing after the emit is dropped — no second event, no fallback.
+            h.Exit("784fcaf5", T0.AddSeconds(1.99));
+            h.Now = T0.AddSeconds(40);
+            h.Flush();
+            Assert.Single(h.Completed);
+        }
+
+        [Fact]
+        public void Shutdown_flush_emits_a_held_result_at_once()
+        {
+            using var h = new Harness();
+            h.Start("a52e4f47", T0);
+            h.Now = T0.AddSeconds(2);
+            h.Result("a52e4f47", T0.AddSeconds(2), "Failed");
+            Assert.Empty(h.Completed);
+
+            h.Flush(force: true);
+            var script = Assert.Single(h.Completed);
+            Assert.Equal("Failed", script.Result);
+            Assert.Null(script.ExitCode);
+        }
+
+        [Fact]
+        public void Late_start_line_of_an_emitted_run_opens_no_new_run()
+        {
+            // Session e7f3c910, 376ee51a: the result was emitted, THEN the executor's start and
+            // exit lines of the same run were read (a 2 s poll stall) — the start opened a second
+            // slot and the exit code became a fallback duplicate 15 s later.
+            using var h = new Harness();
+            h.Start("376ee51a", T0);
+            h.Exit("376ee51a", T0.AddSeconds(1.99));
+            h.Now = T0.AddSeconds(2);
+            h.Result("376ee51a", T0.AddSeconds(2));
+            Assert.Single(h.Completed);
+            Assert.Single(h.Started);
+
+            h.Start("376ee51a", T0.AddMilliseconds(300));
+            Assert.Single(h.Started);
+            h.Exit("376ee51a", T0.AddSeconds(1.99));
+            h.Now = T0.AddSeconds(30);
+            h.Flush();
+            Assert.Single(h.Completed);
+        }
+
+        [Fact]
+        public void Start_line_newer_than_the_emitted_result_is_the_next_run()
+        {
+            using var h = new Harness();
+            h.Start("338d9434", T0);
+            h.Exit("338d9434", T0.AddSeconds(1));
+            h.Now = T0.AddSeconds(1);
+            h.Result("338d9434", T0.AddSeconds(1));
+            Assert.Single(h.Completed);
+
+            // IME re-runs the policy after the user signed in.
+            h.Start("338d9434", T0.AddMinutes(7));
+            Assert.Equal(2, h.Started.Count);
+            h.Exit("338d9434", T0.AddMinutes(7).AddSeconds(3));
+            h.Now = T0.AddMinutes(7).AddSeconds(3);
+            h.Result("338d9434", T0.AddMinutes(7).AddSeconds(3));
+            Assert.Equal(2, h.Completed.Count);
+            Assert.Equal(T0.AddMinutes(7), h.Completed[1].StartedAtUtc);
+        }
+
+        [Fact]
+        public void Newer_start_line_closes_a_held_result_and_starts_the_next_run()
+        {
+            using var h = new Harness();
+            h.Start("c81b8053", T0);
+            h.Now = T0.AddSeconds(2);
+            h.Result("c81b8053", T0.AddSeconds(2));
+            Assert.Empty(h.Completed);
+
+            // The end block never surfaced before the policy ran again.
+            h.Start("c81b8053", T0.AddSeconds(4));
+            var first = Assert.Single(h.Completed);
+            Assert.Null(first.ExitCode);
+            Assert.Equal(T0, first.StartedAtUtc);
+            Assert.Equal(2, h.Started.Count);
+
+            h.Exit("c81b8053", T0.AddSeconds(6));
+            h.Now = T0.AddSeconds(6);
+            h.Result("c81b8053", T0.AddSeconds(6));
+            Assert.Equal(2, h.Completed.Count);
+            Assert.Equal(0, h.Completed[1].ExitCode);
+            Assert.Equal(T0.AddSeconds(4), h.Completed[1].StartedAtUtc);
+        }
+
+        [Fact]
+        public void Result_without_a_start_takes_the_recovered_start_line_and_end_block()
+        {
+            // Both the start block and the end block were hidden when the result arrived; the
+            // ledger rewind the result triggers brings both back on the next pass.
+            using var h = new Harness();
+            h.Now = T0.AddSeconds(2);
+            h.Result("d39eeef3", T0.AddSeconds(2));
+            Assert.Empty(h.Completed);
+
+            h.Start("d39eeef3", T0);
+            Assert.Empty(h.Started);
+            h.Exit("d39eeef3", T0.AddSeconds(1.99));
+            h.Now = T0.AddSeconds(2.2);
+            h.Flush();
+
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(T0, script.StartedAtUtc);
+            Assert.Equal(0, script.ExitCode);
+        }
+
+        [Fact]
+        public void Held_result_survives_a_restart()
+        {
+            using var h = new Harness();
+            h.Start("832e27bc", T0);
+            h.Now = T0.AddSeconds(2);
+            h.Result("832e27bc", T0.AddSeconds(2));
+            h.Restart();
+            Assert.Empty(h.Completed);
+
+            h.Exit("832e27bc", T0.AddSeconds(1.99));
+            h.Now = T0.AddSeconds(2.5);
+            h.Flush();
+            var script = Assert.Single(h.Completed);
+            Assert.Equal(0, script.ExitCode);
+            Assert.Equal(T0.AddSeconds(2), script.ResultObservedAtUtc);
+            Assert.Equal("PS-SCRIPT-RESULT", script.ResultPatternId);
+        }
+
+        [Fact]
+        public void Emitted_marker_keeps_the_run_timestamp_across_a_restart()
+        {
+            using var h = new Harness();
+            h.Start("89b3cbcd", T0);
+            h.Exit("89b3cbcd", T0.AddSeconds(1));
+            h.Now = T0.AddSeconds(1);
+            h.Result("89b3cbcd", T0.AddSeconds(1));
+            h.Restart();
+
+            h.Start("89b3cbcd", T0.AddMilliseconds(500)); // late line of the emitted run
+            Assert.Single(h.Started);
+            h.Start("89b3cbcd", T0.AddMinutes(5));        // the next run
+            Assert.Equal(2, h.Started.Count);
+        }
+
+        [Fact]
+        public void Marker_list_from_an_older_state_file_still_dedups()
+        {
+            using var tmp = new TempDirectory();
+            var persistence = new ImeTrackerStatePersistence(tmp.Path, new AgentLogger(tmp.Path, AgentLogLevel.Info));
+            persistence.Save(new ImeTrackerStateData { PlatformScriptResultEmitted = new List<string> { "policyZ" } });
+
+            var completed = new List<ScriptExecutionState>();
+            var started = new List<ScriptStartedInfo>();
+            var tracker = new ImeLogTracker(tmp.Path, new List<ImeLogPattern>(), new AgentLogger(tmp.Path, AgentLogLevel.Info), stateDirectory: tmp.Path);
+            tracker.OnScriptCompleted = s => completed.Add(s);
+            tracker.OnScriptStarted = s => started.Add(s);
+            tracker.LoadStateForTest();
+
+            tracker.CompletePlatformScriptFromImeResultForTesting("policyZ", "Success", T0);
+            Assert.Empty(completed);
+
+            // Without a timestamp on the marker every start line is a new run, as before.
+            tracker.LastMatchedLogTimestamp = T0;
+            tracker.HandlePlatformScriptStarted("policyZ");
+            Assert.Single(started);
+        }
+
+        [Fact]
+        public void Emitted_marker_is_capped_at_the_clock_so_the_next_run_still_opens_a_slot()
+        {
+            // Session 4377911b: the result line was re-read after an overwrite rewind and resolved
+            // in the reader's zone, one hour ahead of the clock. Stored uncapped, that stamp made
+            // the genuine second run's start line read as a late line of the first run and its
+            // result a duplicate.
+            using var h = new Harness();
+            h.Start("d94468af", T0.AddSeconds(-10));
+            h.Result("d94468af", T0.AddHours(1));
+            h.Exit("d94468af", T0.AddSeconds(-1));
+            h.Flush();
+            Assert.Single(h.Completed);
+
+            // The second run, two minutes later on the clock — still "before" the uncapped stamp.
+            h.Now = T0.AddMinutes(2);
+            h.Start("d94468af", h.Now.AddSeconds(-5));
+            h.Result("d94468af", h.Now.AddSeconds(-1));
+            h.Exit("d94468af", h.Now.AddSeconds(-2));
+            h.Flush();
+
+            Assert.Equal(2, h.Completed.Count);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/ImeLogTrackerScriptStatePersistenceTests.cs

@@ -41,7 +41,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             // Run 1: exit code seen, shutdown force-flush emits the fallback completion.
             var tracker1 = BuildTracker(tmp, out var emitted1);
             tracker1.SeedPendingPlatformScriptForTesting("policyA", exitCode: 0, exitObservedAtUtc: observedAt);
-            tracker1.FlushStalePlatformScriptResults(observedAt.AddSeconds(1), force: true);
+            tracker1.FlushPendingPlatformScriptResults(observedAt.AddSeconds(1), force: true);
             Assert.Single(emitted1);
             tracker1.SaveStateForTest();
 
@@ -68,7 +68,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             // Restarted tracker continues the grace window instead of dropping the script.
             var tracker2 = BuildTracker(tmp, out var emitted2);
             tracker2.LoadStateForTest();
-            tracker2.FlushStalePlatformScriptResults(observedAt.AddSeconds(20));
+            tracker2.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
 
             var script = Assert.Single(emitted2);
             Assert.Equal("policyB", script.PolicyId);
@@ -84,7 +84,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
 
             var tracker1 = BuildTracker(tmp, out _);
             tracker1.SeedPendingPlatformScriptForTesting("policyC", exitCode: 0, exitObservedAtUtc: observedAt);
-            tracker1.FlushStalePlatformScriptResults(observedAt.AddSeconds(1), force: true);
+            tracker1.FlushPendingPlatformScriptResults(observedAt.AddSeconds(1), force: true);
             tracker1.SaveStateForTest();
 
             // Restart, then a genuine RE-RUN of the same policy (fresh start clears the marker).
@@ -108,12 +108,41 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
 
             var tracker = BuildTracker(tmp, out var emitted);
             tracker.LoadStateForTest(); // must not throw
+            Assert.Equal(0, tracker.ParkedPlatformScriptCountForTest);
 
-            // Degrades to pre-fix behavior: no markers restored, normal emission works.
+            // Degrades to pre-fix behavior: no markers restored, normal emission works (the
+            // result waits for its end block until the shutdown flush).
             tracker.CompletePlatformScriptFromImeResultForTesting("policyD", "Success");
+            tracker.FlushPendingPlatformScriptResults(DateTime.UtcNow, force: true);
             Assert.Single(emitted);
         }
 
+        [Fact]
+        public void Pending_slot_from_a_state_file_without_executor_start_loads_and_completes()
+        {
+            using var tmp = new TempDirectory();
+            var started = new DateTime(2026, 10, 4, 9, 0, 0, DateTimeKind.Utc);
+
+            // A pending slot written by an agent before runs carried their executor start and run id.
+            var persistence = new ImeTrackerStatePersistence(tmp.Path, new AgentLogger(tmp.Path, AgentLogLevel.Info));
+            persistence.Save(new ImeTrackerStateData
+            {
+                PendingPlatformScripts = new List<ScriptExecutionState>
+                {
+                    new ScriptExecutionState { PolicyId = "policyF", ScriptType = "platform", StartedAtUtc = started, ExitCode = 0, ExitObservedAtUtc = started.AddSeconds(5), Stdout = "done", Stderr = "" },
+                },
+            });
+
+            var tracker = BuildTracker(tmp, out var emitted);
+            tracker.LoadStateForTest();
+            tracker.CompletePlatformScriptFromImeResultForTesting("policyF", "Success", started.AddSeconds(6));
+
+            var script = Assert.Single(emitted);
+            Assert.Equal("Success", script.Result);
+            Assert.Equal(0, script.ExitCode);
+            Assert.False(string.IsNullOrEmpty(script.RunId));
+        }
+
         [Fact]
         public void Stale_result_older_than_current_run_start_is_dropped()
         {
@@ -128,8 +157,10 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             tracker.CompletePlatformScriptFromImeResultForTesting("policyE", "Failed", run2Start.AddMinutes(-5));
             Assert.Empty(emitted);
 
-            // Run 2's own result (newer than its start) still emits normally.
+            // Run 2's own result (newer than its start) still emits normally — held for the end
+            // block until the shutdown flush, since none is seeded here.
             tracker.CompletePlatformScriptFromImeResultForTesting("policyE", "Success", run2Start.AddMinutes(2));
+            tracker.FlushPendingPlatformScriptResults(run2Start.AddMinutes(2), force: true);
             var script = Assert.Single(emitted);
             Assert.Equal("Success", script.Result);
             Assert.Equal(run2Start, script.StartedAtUtc);
@@ -150,5 +181,45 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
             Assert.False(tracker2.TryClaimScriptTimeoutSuspected("policyF")); // cross-restart dedup
             Assert.True(tracker2.TryClaimScriptTimeoutSuspected("policyG"));  // other policies unaffected
         }
+
+        [Fact]
+        public void Line_provenance_of_a_pending_script_survives_restart()
+        {
+            using var tmp = new TempDirectory();
+            var observedAt = new DateTime(2026, 9, 17, 13, 20, 7, DateTimeKind.Utc);
+            var start = new CmTraceLineProvenance
+            {
+                SourceLocalTs = new DateTime(2026, 9, 17, 15, 19, 57, DateTimeKind.Unspecified),
+                Origin = CmTraceOffsetOrigin.LineAnchored,
+                OffsetMinutes = 120,
+                MeasuredWriterOffsetMinutes = 120,
+                SourceFileName = "IntuneManagementExtension.log",
+            };
+            var exit = new CmTraceLineProvenance
+            {
+                SourceLocalTs = new DateTime(2026, 9, 17, 15, 20, 7, DateTimeKind.Unspecified),
+                Origin = CmTraceOffsetOrigin.None,
+                OffsetMinutes = 60,
+                SourceFileName = "AgentExecutor.log",
+            };
+
+            var tracker1 = BuildTracker(tmp, out _);
+            tracker1.SeedPendingPlatformScriptForTesting("policyH", exitCode: 0, exitObservedAtUtc: observedAt,
+                startedAtUtc: observedAt.AddSeconds(-10), startedAtProvenance: start, exitProvenance: exit);
+            tracker1.SaveStateForTest();
+
+            var tracker2 = BuildTracker(tmp, out var emitted2);
+            tracker2.LoadStateForTest();
+            tracker2.FlushPendingPlatformScriptResults(observedAt.AddSeconds(20));
+
+            var script = Assert.Single(emitted2);
+            Assert.Equal(CmTraceOffsetOrigin.LineAnchored, script.StartedAtProvenance.Origin);
+            Assert.Equal(120, script.StartedAtProvenance.OffsetMinutes);
+            Assert.Equal(start.SourceLocalTs, script.StartedAtProvenance.SourceLocalTs);
+            Assert.Equal(DateTimeKind.Unspecified, script.StartedAtProvenance.SourceLocalTs!.Value.Kind); // no zone was ever attached
+            Assert.Equal("AgentExecutor.log", script.ExitProvenance.SourceFileName);
+            Assert.Equal(60, script.ExitProvenance.OffsetMinutes);
+            Assert.Null(script.ResultProvenance);
+        }
     }
 }

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Ime/RecurringScriptGateTests.cs

@@ -0,0 +1,267 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Newtonsoft.Json;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Ime
+{
+    /// <summary>
+    /// IME re-runs health-script policies on its own schedule for as long as the device is up.
+    /// A session that waited days for its user reported every hourly run of every policy
+    /// (field: 9 policies × 94 runs in one session). The gate emits the first run and every
+    /// changed result, counts the rest, and keeps the start/result pairing intact that the
+    /// running indicators rely on.
+    /// </summary>
+    public sealed class RecurringScriptGateTests
+    {
+        private const string Policy = "11111111-2222-3333-4444-555555555555";
+        private static readonly DateTime T0 = new DateTime(2026, 9, 16, 20, 0, 0, DateTimeKind.Utc);
+
+        private static ScriptExecutionState Early(string compliance, int exit = 0, string? stderr = null) =>
+            new ScriptExecutionState
+            {
+                PolicyId = Policy, ScriptType = "remediation", ScriptPart = "detection",
+                ComplianceResult = compliance, ExitCode = exit, Stderr = stderr, DurationBasis = "script_runtime",
+            };
+
+        private static ScriptExecutionState Consolidated(string compliance, int exit = 0, int status = 1) =>
+            new ScriptExecutionState
+            {
+                PolicyId = Policy, ScriptType = "remediation", ScriptPart = "detection",
+                ComplianceResult = compliance, ExitCode = exit, RemediationStatus = status,
+                DurationBasis = "cycle_including_reporting_latency",
+            };
+
+        [Fact]
+        public void First_run_emits_start_and_result()
+        {
+            var gate = new RecurringScriptGate();
+
+            Assert.True(gate.OnStart(Policy, T0, "6", "HS-SCRIPT-START"));
+            Assert.True(gate.OnResult(Early("True"), T0.AddSeconds(5), out var released));
+            Assert.Null(released);
+        }
+
+        [Fact]
+        public void Repeated_result_is_counted_and_its_start_stays_held()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "HS-SCRIPT-START");
+            gate.OnResult(Early("True"), T0.AddSeconds(5), out _);
+
+            Assert.False(gate.OnStart(Policy, T0.AddHours(1), "6", "HS-SCRIPT-START"));
+            Assert.False(gate.OnResult(Early("True"), T0.AddHours(1).AddSeconds(5), out var released));
+            Assert.Null(released);
+
+            var summary = Assert.Single(gate.TakeSummaries());
+            Assert.Equal(2, summary.RunsObserved);
+            Assert.Equal(1, summary.RunsCollapsed);
+            Assert.Equal(1, summary.CollapsedResults);
+            Assert.Equal(T0.AddHours(1).AddSeconds(5), summary.LastCollapsedAtUtc);
+        }
+
+        [Fact]
+        public void Changed_result_releases_the_held_start_with_its_own_timestamp()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "HS-SCRIPT-START");
+            gate.OnResult(Early("True"), T0.AddSeconds(5), out _);
+
+            var secondStart = T0.AddHours(1);
+            gate.OnStart(Policy, secondStart, "6", "HS-SCRIPT-START");
+            Assert.True(gate.OnResult(Early("False", exit: 1), secondStart.AddSeconds(5), out var released));
+
+            Assert.NotNull(released);
+            Assert.Equal(Policy, released.PolicyId);
+            Assert.Equal(secondStart, released.SourceTimestampUtc);
+            Assert.Equal("HS-SCRIPT-START", released.PatternId);
+            Assert.Equal("6", released.PolicyType);
+            Assert.Empty(gate.TakeSummaries());
+        }
+
+        [Fact]
+        public void New_stderr_counts_as_a_changed_result()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            gate.OnResult(Early("True"), T0, out _);
+
+            gate.OnStart(Policy, T0.AddHours(1), "6", "p");
+            Assert.True(gate.OnResult(Early("True", stderr: "Get-ChildItem : path not found"), T0.AddHours(1), out _));
+        }
+
+        [Fact]
+        public void Early_signal_and_consolidated_result_do_not_overwrite_each_other()
+        {
+            // Both describe the detection phase, but only the consolidated one knows
+            // RemediationStatus. Sharing one signature slot would make every run look changed.
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            Assert.True(gate.OnResult(Early("True"), T0, out _));
+            Assert.True(gate.OnResult(Consolidated("True"), T0.AddMinutes(1), out _));
+
+            gate.OnStart(Policy, T0.AddHours(1), "6", "p");
+            Assert.False(gate.OnResult(Early("True"), T0.AddHours(1), out _));
+            Assert.False(gate.OnResult(Consolidated("True"), T0.AddHours(1).AddMinutes(1), out _));
+        }
+
+        [Fact]
+        public void Held_start_without_result_is_released_only_after_the_grace()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            gate.OnResult(Early("True"), T0, out _);
+            var heldAt = T0.AddHours(1);
+            gate.OnStart(Policy, heldAt, "6", "p");
+
+            Assert.Empty(gate.ReleaseStartsWithoutResult(heldAt.AddMinutes(29), TimeSpan.FromMinutes(30)));
+
+            var released = Assert.Single(gate.ReleaseStartsWithoutResult(heldAt.AddMinutes(31), TimeSpan.FromMinutes(30)));
+            Assert.Equal(heldAt, released.SourceTimestampUtc);
+            Assert.Empty(gate.ReleaseStartsWithoutResult(heldAt.AddHours(2), TimeSpan.FromMinutes(30)));
+        }
+
+        [Fact]
+        public void Held_start_whose_result_was_collapsed_is_never_released_as_unfinished()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            gate.OnResult(Early("True"), T0, out _);
+            gate.OnStart(Policy, T0.AddHours(1), "6", "p");
+            gate.OnResult(Early("True"), T0.AddHours(1), out _);
+
+            Assert.Empty(gate.ReleaseStartsWithoutResult(T0.AddDays(1), TimeSpan.FromMinutes(30)));
+        }
+
+        [Fact]
+        public void Run_superseded_by_the_next_start_counts_as_without_result()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            gate.OnResult(Early("True"), T0, out _);
+            gate.OnStart(Policy, T0.AddHours(1), "6", "p");   // no result
+            gate.OnStart(Policy, T0.AddHours(2), "6", "p");
+            gate.OnResult(Early("True"), T0.AddHours(2), out _);
+
+            var summary = Assert.Single(gate.TakeSummaries());
+            Assert.Equal(3, summary.RunsObserved);
+            Assert.Equal(1, summary.RunsWithoutResult);
+            Assert.Equal(1, summary.RunsCollapsed);
+        }
+
+        [Fact]
+        public void Summary_reports_growth_only()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            gate.OnResult(Early("True"), T0, out _);
+            gate.OnStart(Policy, T0.AddHours(1), "6", "p");
+            gate.OnResult(Early("True"), T0.AddHours(1), out _);
+
+            Assert.Single(gate.TakeSummaries());
+            Assert.Empty(gate.TakeSummaries());
+
+            gate.OnStart(Policy, T0.AddHours(2), "6", "p");
+            gate.OnResult(Early("True"), T0.AddHours(2), out _);
+            Assert.Equal(2, Assert.Single(gate.TakeSummaries()).RunsCollapsed);
+        }
+
+        [Fact]
+        public void State_round_trips_through_json()
+        {
+            var gate = new RecurringScriptGate();
+            gate.OnStart(Policy, T0, "6", "p");
+            gate.OnResult(Early("True"), T0, out _);
+            gate.OnStart(Policy, T0.AddHours(1), "6", "p");
+
+            var json = JsonConvert.SerializeObject(gate.ToPersisted());
+            var restored = new RecurringScriptGate();
+            restored.Restore(JsonConvert.DeserializeObject<Dictionary<string, RecurringScriptPolicyState>>(json));
+
+            // The restored gate still knows the last report and still holds the second start.
+            Assert.True(restored.OnResult(Early("False", exit: 1), T0.AddHours(1).AddSeconds(5), out var released));
+            Assert.Equal(T0.AddHours(1), released.SourceTimestampUtc);
+        }
+
+        // ── Through the tracker ───────────────────────────────────────────────────
+
+        private sealed class Rig
+        {
+            public readonly List<ScriptStartedInfo> Started = new List<ScriptStartedInfo>();
+            public readonly List<ScriptExecutionState> Completed = new List<ScriptExecutionState>();
+            public readonly List<ScriptRecurrenceSummary> Summaries = new List<ScriptRecurrenceSummary>();
+            public readonly ImeLogTracker Tracker;
+
+            public Rig(TempDirectory tmp)
+            {
+                Tracker = new ImeLogTracker(
+                    logFolder: tmp.Path,
+                    patterns: new List<ImeLogPattern>(),
+                    logger: new AgentLogger(tmp.Path, AgentLogLevel.Info),
+                    stateDirectory: tmp.Path);
+                Tracker.OnScriptStarted = Started.Add;
+                Tracker.OnScriptCompleted = Completed.Add;
+                Tracker.OnScriptRecurrenceSummary = Summaries.Add;
+            }
+
+            public void Run(DateTime startedAtUtc, string compliance)
+            {
+                Tracker.HandleHealthScriptStartForTest(Policy, startedAtUtc);
+                Tracker.HandleHealthScriptDetectionResultForTest(Policy, compliance, "pre", exitCode: compliance == "True" ? 0 : 1);
+            }
+        }
+
+        [Fact]
+        public void Tracker_collapses_repeats_across_a_restart_and_reports_them_on_stop()
+        {
+            using var tmp = new TempDirectory();
+
+            var first = new Rig(tmp);
+            first.Run(T0, "True");
+            first.Run(T0.AddHours(1), "True");
+            Assert.Single(first.Started);
+            Assert.Single(first.Completed);
+            first.Tracker.SaveStateForTest();
+
+            // Restart (reboot kill, WhiteGlove Part 2): the last report and the counter are back.
+            var second = new Rig(tmp);
+            second.Tracker.LoadStateForTest();
+            second.Run(T0.AddHours(2), "True");
+            Assert.Empty(second.Started);
+            Assert.Empty(second.Completed);
+
+            second.Run(T0.AddHours(3), "False");
+            var start = Assert.Single(second.Started);
+            Assert.Equal(T0.AddHours(3), start.SourceTimestampUtc);
+            Assert.Equal("False", Assert.Single(second.Completed).ComplianceResult);
+
+            second.Tracker.FlushRecurringScripts(T0.AddHours(4), shuttingDown: true);
+            var summary = Assert.Single(second.Summaries);
+            Assert.Equal(4, summary.RunsObserved);
+            Assert.Equal(2, summary.RunsCollapsed);
+        }
+
+        [Fact]
+        public void Tracker_leaves_platform_scripts_alone()
+        {
+            using var tmp = new TempDirectory();
+            var rig = new Rig(tmp);
+            var observedAt = T0;
+
+            for (var run = 0; run < 2; run++)
+            {
+                rig.Tracker.SeedPendingPlatformScriptForTesting("platformA", exitCode: 0, exitObservedAtUtc: observedAt.AddMinutes(run * 10));
+                rig.Tracker.CompletePlatformScriptFromImeResultForTesting("platformA", "Success", observedAt.AddMinutes(run * 10 + 1));
+            }
+
+            Assert.Equal(2, rig.Completed.Count(s => s.ScriptType == "platform"));
+            rig.Tracker.FlushRecurringScripts(T0.AddDays(1), shuttingDown: true);
+            Assert.Empty(rig.Summaries);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Runtime/DiagnosticsEventLogBlockTests.cs

@@ -0,0 +1,204 @@
+#nullable enable
+using System.Collections.Generic;
+using System.IO;
+using System.IO.Compression;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Configuration;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Runtime;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Telemetry.Gather;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Transport;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Runtime
+{
+    /// <summary>
+    /// The hard-blocked event-log channels (Security, PowerShell, Sysmon) are unreadable through
+    /// the diagnostics package as well — by path, by wildcard, by resolved channel, and in
+    /// unrestricted mode. Before this the block held only in the event-log collector.
+    /// </summary>
+    public sealed class DiagnosticsEventLogBlockTests
+    {
+        private const string WinevtLogs = @"C:\Windows\System32\winevt\Logs";
+
+        // A channel no machine has: the export fails and the packager falls back to the raw copy.
+        private const string HarmlessChannel = "AutopilotMonitor-Tests-NoSuchChannel/Operational";
+
+        [Theory]
+        [InlineData("Security.evtx")]
+        [InlineData("security.EVTX")]
+        [InlineData("Microsoft-Windows-PowerShell%4Operational.evtx")]
+        [InlineData("Microsoft-Windows-PowerShell%4Admin.evtx")]
+        [InlineData("Windows PowerShell.evtx")]
+        [InlineData("Microsoft-Windows-Sysmon%4Operational.evtx")]
+        [InlineData("Archive-Security-2026-09-21-10-15-30-123.evtx")]
+        [InlineData("Archive-Microsoft-Windows-PowerShell%4Operational-2026-09-21-10-15-30-123.evtx")]
+        public void Hard_blocked_channel_files_are_recognised_by_name(string fileName)
+        {
+            Assert.True(DiagnosticsPathGuards.IsHardBlockedEventLogFile(Path.Combine(WinevtLogs, fileName)));
+        }
+
+        [Theory]
+        [InlineData("System.evtx")]
+        [InlineData("Application.evtx")]
+        [InlineData("SecurityAudit.evtx")]
+        [InlineData("Security.log")]
+        [InlineData("Microsoft-Windows-Security-Mitigations%4KernelMode.evtx")]
+        // Same boundary as the collector: only '/' continues a blocked channel name.
+        [InlineData("Microsoft-Windows-PowerShell-DesiredStateConfiguration-FileDownloadManager%4Operational.evtx")]
+        [InlineData("Archive-System-2026-09-21-10-15-30-123.evtx")]
+        public void Other_files_are_not_mistaken_for_a_blocked_channel(string fileName)
+        {
+            Assert.False(DiagnosticsPathGuards.IsHardBlockedEventLogFile(Path.Combine(WinevtLogs, fileName)));
+        }
+
+        [Theory]
+        [InlineData(false)]
+        [InlineData(true)]
+        public void Path_guard_refuses_a_blocked_channel_file_in_every_mode(bool unrestrictedMode)
+        {
+            Assert.False(DiagnosticsPathGuards.IsDiagnosticsPathAllowed(
+                WinevtLogs + @"\Security.evtx", unrestrictedMode));
+            Assert.False(DiagnosticsPathGuards.IsDiagnosticsPathAllowed(
+                WinevtLogs + @"\Microsoft-Windows-PowerShell%4Operational.evtx", unrestrictedMode));
+        }
+
+        [Fact]
+        public void Path_guard_still_admits_other_channels_and_wildcards()
+        {
+            Assert.True(DiagnosticsPathGuards.IsDiagnosticsPathAllowed(WinevtLogs + @"\System.evtx"));
+            // Undecidable on the string — the packager filters per file (tests below).
+            Assert.True(DiagnosticsPathGuards.IsDiagnosticsPathAllowed(WinevtLogs + @"\*.evtx"));
+        }
+
+        [Theory]
+        [InlineData("Security", true)]
+        [InlineData("Microsoft-Windows-PowerShell/Operational", true)]
+        [InlineData(" Windows PowerShell ", true)]
+        [InlineData("Microsoft-Windows-Sysmon/Operational", true)]
+        [InlineData("System", false)]
+        [InlineData("", false)]
+        [InlineData(null, false)]
+        public void Channel_block_is_one_matcher_for_collector_and_package(string? channel, bool blocked)
+        {
+            Assert.Equal(blocked, GatherRuleGuards.IsHardBlockedEventLogChannel(channel!));
+        }
+
+        // ------------------------------------------------------------ packager ----
+
+        // %TEMP% lives under C:\Users, which the path guard blocks in every mode, so the
+        // configured folder sits beside the test assembly and the run is unrestricted — which
+        // is also the strongest form of the claim: not even unrestricted mode collects these.
+        private sealed class EvtxFolder : System.IDisposable
+        {
+            public string Path { get; } = System.IO.Path.Combine(
+                System.AppContext.BaseDirectory, "diag-evtx-" + System.Guid.NewGuid().ToString("N"));
+
+            public EvtxFolder(params string[] fileNames)
+            {
+                Directory.CreateDirectory(Path);
+                foreach (var name in fileNames)
+                    File.WriteAllBytes(System.IO.Path.Combine(Path, name), new byte[] { 1, 2, 3 });
+            }
+
+            public void Dispose()
+            {
+                try { Directory.Delete(Path, recursive: true); } catch { }
+            }
+        }
+
+        private static DiagnosticsPackageService BuildService(
+            TempDirectory scratch, string configuredPath, System.Func<string, string> channelResolver)
+        {
+            var logger = new AgentLogger(Directory.CreateDirectory(Path.Combine(scratch.Path, "logs")).FullName);
+            var apiClient = new BackendApiClient(
+                httpClient: new System.Net.Http.HttpClient(),
+                baseUrl: "http://localhost",
+                manufacturer: string.Empty,
+                model: string.Empty,
+                serialNumber: string.Empty,
+                useBootstrapTokenAuth: false,
+                bootstrapToken: null,
+                agentVersion: "0.0.0",
+                logger: logger);
+
+            var cfg = new AgentConfiguration
+            {
+                SessionId = "S1",
+                TenantId = "T1",
+                ApiBaseUrl = "http://localhost",
+                UnrestrictedMode = true,
+            };
+            cfg.DiagnosticsLogPaths.Add(new DiagnosticsLogPath { Path = configuredPath });
+
+            string Sub(string name) => Directory.CreateDirectory(Path.Combine(scratch.Path, name)).FullName;
+            return new DiagnosticsPackageService(
+                cfg,
+                logger,
+                apiClient,
+                agentLogFolderOverride: Sub("agentlogs"),
+                imeLogFolderOverride: Sub("ime"),
+                agentStateFolderOverride: Sub("state"),
+                agentSpoolFolderOverride: Sub("spool"),
+                agentDataFolderOverride: Sub("data"),
+                sectionFolderOverrides: null,
+                devicePreparationProbe: () => false)
+            {
+                EventLogChannelResolver = channelResolver,
+            };
+        }
+
+        private static List<string> ZipEntryNames(byte[] bytes)
+        {
+            using var ms = new MemoryStream(bytes);
+            using var archive = new ZipArchive(ms, ZipArchiveMode.Read);
+            return archive.Entries.Select(e => e.FullName).ToList();
+        }
+
+        private static string ReadManifest(byte[] bytes)
+        {
+            using var ms = new MemoryStream(bytes);
+            using var archive = new ZipArchive(ms, ZipArchiveMode.Read);
+            using var reader = new StreamReader(archive.GetEntry("package-manifest.txt")!.Open());
+            return reader.ReadToEnd();
+        }
+
+        [Fact]
+        public void Wildcard_entry_skips_blocked_channel_files_and_keeps_the_rest()
+        {
+            using var scratch = new TempDirectory();
+            using var folder = new EvtxFolder(
+                "Security.evtx", "Microsoft-Windows-PowerShell%4Operational.evtx", "Setup.evtx");
+
+            var service = BuildService(scratch, Path.Combine(folder.Path, "*.evtx"), _ => HarmlessChannel);
+            var bytes = service.BuildArchiveBytes(enrollmentSucceeded: false);
+
+            var entries = ZipEntryNames(bytes);
+            Assert.Contains(entries, e => e.EndsWith("/Setup.evtx"));
+            Assert.DoesNotContain(entries, e => e.EndsWith("Security.evtx"));
+            Assert.DoesNotContain(entries, e => e.Contains("PowerShell"));
+
+            var manifest = ReadManifest(bytes);
+            Assert.Contains("BLOCKED (event-log channel guard", manifest);
+            Assert.Contains("Security.evtx", manifest);
+            Assert.Equal(2, service.LastPackaging!.ProblemsByKind["path-guard"]);
+        }
+
+        [Fact]
+        public void File_with_a_harmless_name_is_blocked_when_it_resolves_to_a_blocked_channel()
+        {
+            // A channel is free to write to any file name; and the resolver's naming fallback
+            // maps a stray file onto a live channel. The export must never read that channel.
+            using var scratch = new TempDirectory();
+            using var folder = new EvtxFolder("Harmless.evtx");
+
+            var service = BuildService(scratch, Path.Combine(folder.Path, "Harmless.evtx"), _ => "Security");
+            var bytes = service.BuildArchiveBytes(enrollmentSucceeded: false);
+
+            Assert.DoesNotContain(ZipEntryNames(bytes), e => e.EndsWith("Harmless.evtx"));
+            Assert.Contains("BLOCKED (event-log channel guard, channel 'Security')", ReadManifest(bytes));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Runtime/DiagnosticsPackageServiceTests.cs

@@ -19,6 +19,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Runtime
     /// completion markers (whiteglove.complete, clean-exit) — V1 sessions had only AgentLogs/
     /// and ImeLogs/, which left forensics blind to decision-engine state and pending uploads.
     /// </summary>
+    [Collection(UserProfileResolverCollection.Name)] // replaces UserProfileResolver's static state
     public sealed class DiagnosticsPackageServiceTests
     {
         private static AgentConfiguration Cfg(string sessionId = "S1") => new AgentConfiguration
@@ -206,6 +207,91 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Runtime
             Assert.Contains($"BLOCKED (path guard): {configuredPath}", manifest);
         }
 
+        // %TEMP% lives under C:\Users, which the guard blocks in every mode — the positive
+        // configured-path cases run beside the test assembly, in unrestricted mode.
+        private sealed class ConfiguredPathTree : System.IDisposable
+        {
+            public string Root { get; } = Path.Combine(
+                System.AppContext.BaseDirectory, "diag-paths-" + System.Guid.NewGuid().ToString("N"));
+            public string Logs => Path.Combine(Root, "Logs");
+
+            public ConfiguredPathTree()
+            {
+                Directory.CreateDirectory(Path.Combine(Logs, "sub"));
+                File.WriteAllText(Path.Combine(Root, "parent-only.txt"), "not configured");
+                File.WriteAllText(Path.Combine(Logs, "app.log"), "configured");
+                File.WriteAllText(Path.Combine(Logs, "sub", "app.log"), "below");
+            }
+
+            public void Dispose()
+            {
+                try { Directory.Delete(Root, recursive: true); } catch { /* best effort */ }
+            }
+        }
+
+        [Theory]
+        [InlineData("")]
+        [InlineData("\\")]
+        public void BuildArchiveBytes_folder_entry_collects_the_folder_not_its_parent(string trailing)
+        {
+            using var rig = new Rig();
+            using var tree = new ConfiguredPathTree();
+
+            var bytes = rig.Build(cfg =>
+                {
+                    cfg.UnrestrictedMode = true;
+                    cfg.DiagnosticsLogPaths.Add(new AutopilotMonitor.Shared.Models.DiagnosticsLogPath
+                    {
+                        Path = tree.Logs + trailing,
+                        IncludeSubfolders = true,
+                    });
+                })
+                .BuildArchiveBytes(enrollmentSucceeded: true);
+
+            var entries = ZipEntryNames(bytes);
+            Assert.Contains("AdditionalLogs/Logs/app.log", entries);
+            Assert.Contains("AdditionalLogs/Logs/sub/app.log", entries);
+            Assert.DoesNotContain(entries, e => e.EndsWith("parent-only.txt"));
+        }
+
+        [Fact]
+        public void BuildArchiveBytes_file_entry_ignores_include_subfolders()
+        {
+            using var rig = new Rig();
+            using var tree = new ConfiguredPathTree();
+
+            var bytes = rig.Build(cfg =>
+                {
+                    cfg.UnrestrictedMode = true;
+                    cfg.DiagnosticsLogPaths.Add(new AutopilotMonitor.Shared.Models.DiagnosticsLogPath
+                    {
+                        Path = Path.Combine(tree.Logs, "app.log"),
+                        IncludeSubfolders = true,
+                    });
+                })
+                .BuildArchiveBytes(enrollmentSucceeded: true);
+
+            var entries = ZipEntryNames(bytes);
+            Assert.Contains("AdditionalLogs/Logs/app.log", entries);
+            Assert.DoesNotContain("AdditionalLogs/Logs/sub/app.log", entries);
+        }
+
+        [Fact]
+        public void EnumerateFilesNoReparseDirs_asks_the_guard_before_entering_a_subfolder()
+        {
+            using var tree = new ConfiguredPathTree();
+            var refused = new List<string>();
+
+            var files = DiagnosticsPackageService.EnumerateFilesNoReparseDirs(
+                tree.Root, "*", recurse: true,
+                mayEnterDirectory: dir => !dir.EndsWith("sub"),
+                refusedDirectories: refused);
+
+            Assert.Contains(Path.Combine(tree.Logs, "app.log"), files);
+            Assert.DoesNotContain(Path.Combine(tree.Logs, "sub", "app.log"), files);
+            Assert.Equal(new[] { Path.Combine(tree.Logs, "sub") }, refused);
+        }
+
         [Fact]
         public void BuildArchiveBytes_excludes_top_level_session_id_and_bootstrap_config()
         {

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/Runtime/UserProfileResolverTests.cs

@@ -0,0 +1,96 @@
+using System;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Runtime;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.Runtime
+{
+    /// <summary>
+    /// Serialises the test classes that replace <see cref="UserProfileResolver"/>'s static state.
+    /// </summary>
+    [CollectionDefinition(Name)]
+    public sealed class UserProfileResolverCollection
+    {
+        public const string Name = "UserProfileResolver";
+    }
+
+    /// <summary>
+    /// The agent starts before anyone has signed in. A lookup in that window must not pin
+    /// "no user" for the rest of the process — the %LOGGED_ON_USER_PROFILE% gather rules and the
+    /// RealmJoin user logs of the diagnostics package would never resolve.
+    /// </summary>
+    [Collection(UserProfileResolverCollection.Name)]
+    public sealed class UserProfileResolverTests : IDisposable
+    {
+        private static readonly DateTime Start = new DateTime(2026, 9, 28, 12, 0, 0, DateTimeKind.Utc);
+
+        public void Dispose() => UserProfileResolver.Reset();
+
+        [Fact]
+        public void User_who_signs_in_after_the_first_lookup_is_found_later()
+        {
+            string? signedIn = null;
+            var now = Start;
+            UserProfileResolver.SetDetectorForTesting(() => signedIn, () => now);
+
+            Assert.Null(UserProfileResolver.GetLoggedOnUserProfilePath());
+
+            signedIn = @"C:\Users\enduser";
+            now += UserProfileResolver.RetryInterval;
+
+            Assert.Equal(@"C:\Users\enduser", UserProfileResolver.GetLoggedOnUserProfilePath());
+        }
+
+        [Fact]
+        public void No_user_is_detected_again_only_after_the_retry_interval()
+        {
+            var detections = 0;
+            var now = Start;
+            UserProfileResolver.SetDetectorForTesting(() => { detections++; return null; }, () => now);
+
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+            now += TimeSpan.FromSeconds(10);
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+            Assert.Equal(1, detections);
+
+            now += UserProfileResolver.RetryInterval;
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+            Assert.Equal(2, detections);
+        }
+
+        [Fact]
+        public void A_clock_stepping_backwards_does_not_delay_the_next_detection()
+        {
+            var detections = 0;
+            var now = Start;
+            UserProfileResolver.SetDetectorForTesting(() => { detections++; return null; }, () => now);
+
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+            now -= TimeSpan.FromHours(1);   // OOBE time sync
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+
+            Assert.Equal(2, detections);
+        }
+
+        [Fact]
+        public void A_found_user_is_kept_without_detecting_again()
+        {
+            var detections = 0;
+            UserProfileResolver.SetDetectorForTesting(() => { detections++; return @"C:\Users\enduser"; }, () => Start);
+
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+            UserProfileResolver.GetLoggedOnUserProfilePath();
+
+            Assert.Equal(1, detections);
+        }
+
+        [Fact]
+        public void Pinned_no_user_stays_null_without_real_detection()
+        {
+            UserProfileResolver.SetForTesting(null!);
+
+            Assert.Null(UserProfileResolver.GetLoggedOnUserProfilePath());
+            Assert.Null(UserProfileResolver.ExpandCustomTokens(@"%LOGGED_ON_USER_PROFILE%\AppData\Local\x.log"));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/ShellCoreTrackerBreadcrumbTests.cs

@@ -0,0 +1,446 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.Shared;
+using AutopilotMonitor.Shared.Models;
+using Newtonsoft.Json;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
+{
+    /// <summary>
+    /// CloudExperienceHost navigation (D-310): one agent.log line per page start/stop and per
+    /// update-page event name, and for the OOBE update page itself (<c>OobeNDUP</c>,
+    /// <c>RebootNDUP</c>) the <c>oobe_update_page</c> telemetry plus the registry state at its live
+    /// start and stop. Descriptions follow the Shell-Core manifest templates; a 62407 value
+    /// (URLs with tenant ids) leaves the tracker only as a boolean, an integer or an HRESULT.
+    /// </summary>
+    public sealed class ShellCoreTrackerBreadcrumbTests : IDisposable
+    {
+        private static readonly DateTime At = new DateTime(2026, 10, 2, 9, 0, 0, DateTimeKind.Utc);
+
+        private const string NdupStarted = "CloudExperienceHost Web App Activity started. CXID: 'OobeNDUP'.";
+        private const string EspPageStarted = "CloudExperienceHost Web App Activity started. CXID: 'MDMProgressAfterAADRefactored'.";
+        private const string PageStopped = "CloudExperienceHost Web App Activity stopped. Result: 'success'.";
+        private const string ScanStartedName = "CloudExperienceHost Web App Event 1. Name: 'ExpeditedUpdate_startWUScanStarted'.";
+        private const string NavigateWithTenantUrl =
+            "CloudExperienceHost Web App Event 2. Name: 'Navigate', Value: '{\"httpMethod\":\"GET\",\"url\":\"https://login.microsoftonline.com/00000000-0000-0000-0000-000000000000/oauth2/authorize\"}'.";
+        private const string DownloadSucceededWithValue =
+            "CloudExperienceHost Web App Event 2. Name: 'ExpeditedUpdate_commitExpeditionDownloadInstallAsyncSucceeded', Value: '{\"url\":\"https://login.microsoftonline.com/x\"}'.";
+        private const string CspGateTrue =
+            "CloudExperienceHost Web App Event 2. Name: 'ExpeditedUpdate_isNDUPAllowedByCSPSucceeded', Value: 'true'.";
+
+        // A French Windows labels the same fields "Résultat", "Nom" and "valeur" and quotes them
+        // in guillemets; the event properties carry the values unchanged in every language.
+        private const string FrenchNdupStarted = "Activité d’application web CloudExperienceHost démarrée. CXID : « OobeNDUP ».";
+        private const string FrenchPageStopped = "Activité d’application web CloudExperienceHost arrêtée. Résultat : « success ».";
+        private const string FrenchCspGate =
+            "Événement d’application web CloudExperienceHost 2. Nom : « ExpeditedUpdate_isNDUPAllowedByCSPSucceeded », valeur : « true ».";
+
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly FakeSignalIngressSink _sink = new FakeSignalIngressSink();
+        private IReadOnlyList<OobeUpdateRegistrySnapshot.KeyState> _registry = Array.Empty<OobeUpdateRegistrySnapshot.KeyState>();
+
+        public void Dispose() => _tmp.Dispose();
+
+        private ShellCoreTracker Build(string? stateDirectory = null) =>
+            new ShellCoreTracker("S1", "T1",
+                new InformationalEventPost(_sink, new VirtualClock(At)),
+                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                helloTracker: null,
+                oobeUpdateRegistryReader: () => _registry,
+                stateDirectory: stateDirectory);
+
+        private string StateDirectory => Path.Combine(_tmp.Path, "state");
+
+        private static void Live(ShellCoreTracker tracker, int eventId, string description, DateTime at, long recordId) =>
+            tracker.ProcessEvent(eventId, description, at, "Microsoft-Windows-Shell-Core", isBackfill: false, recordId: recordId);
+
+        private IReadOnlyList<FakeSignalIngressSink.PostedSignal> ByType(string eventType) =>
+            _sink.Posted.Where(p =>
+                p.Kind == DecisionSignalKind.InformationalEvent
+                && p.Payload != null
+                && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                && et == eventType).ToList();
+
+        private static IReadOnlyDictionary<string, object> Data(FakeSignalIngressSink.PostedSignal posted) =>
+            (IReadOnlyDictionary<string, object>)posted.TypedPayload!;
+
+        private static OobeUpdateRegistrySnapshot.KeyState NdupKey(string line) =>
+            new OobeUpdateRegistrySnapshot.KeyState("setupOobeNdup", @"SOFTWARE\Microsoft\Windows\CurrentVersion\Setup\OOBE\NDUP",
+                exists: true, hasValues: true, line: line);
+
+        // ------------------------------------------------------------- breadcrumbs ----
+
+        [Fact]
+        public void PageStart_NamesTheCxid()
+        {
+            Assert.Equal("CXH page started: OobeNDUP",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, lastPage: null));
+        }
+
+        [Fact]
+        public void PageStop_IsAttributedToTheLastStartedPage()
+        {
+            // 62405 names no page — it ends the one started last.
+            Assert.Equal("CXH page stopped: OobeNDUP (result=success)",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, lastPage: "OobeNDUP"));
+            Assert.Equal("CXH page stopped: ? (result=success)",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, lastPage: null));
+        }
+
+        [Fact]
+        public void UpdatePageEventNames_AreLogged_FromBothEventIds()
+        {
+            Assert.Equal("CXH event: ExpeditedUpdate_startWUScanStarted",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, lastPage: null));
+            Assert.Equal("CXH event: ExpeditedUpdate_commitExpeditionDownloadInstallAsyncSucceeded",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppEvent, DownloadSucceededWithValue, lastPage: null));
+        }
+
+        [Fact]
+        public void UnsafeEventValues_NeverReachTheLog()
+        {
+            var crumb = ShellCoreTracker.FormatCxhBreadcrumb(
+                ShellCoreTracker.EventId_ShellCore_WebAppEvent, DownloadSucceededWithValue, lastPage: null);
+
+            Assert.NotNull(crumb);
+            Assert.DoesNotContain("microsoftonline", crumb);
+            Assert.DoesNotContain("url", crumb!, StringComparison.OrdinalIgnoreCase);
+        }
+
+        [Fact]
+        public void SafeEventValues_AreLogged()
+        {
+            Assert.Equal("CXH event: ExpeditedUpdate_isNDUPAllowedByCSPSucceeded (value=true)",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppEvent, CspGateTrue, lastPage: null));
+        }
+
+        [Fact]
+        public void OtherEventNames_AreNotLogged()
+        {
+            // Ordinary page traffic (Navigate, Visible, ESP progress) stays out of the log.
+            Assert.Null(ShellCoreTracker.FormatCxhBreadcrumb(
+                ShellCoreTracker.EventId_ShellCore_WebAppEvent, NavigateWithTenantUrl, lastPage: "OobeNDUP"));
+            Assert.Null(ShellCoreTracker.FormatCxhBreadcrumb(
+                ShellCoreTracker.EventId_ShellCore_WebAppEvent, "CommercialOOBE_ESPProgress_Page_Exiting", lastPage: null));
+        }
+
+        [Theory]
+        [InlineData("")]
+        [InlineData("CloudExperienceHost Web App Activity started.")]
+        public void PageStartWithoutCxid_IsNoBreadcrumb(string description)
+        {
+            Assert.Null(ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppStarted, description, lastPage: null));
+        }
+
+        [Fact]
+        public void LongTokens_AreBounded()
+        {
+            var longCxid = new string('X', 500);
+            var crumb = ShellCoreTracker.FormatCxhBreadcrumb(
+                ShellCoreTracker.EventId_ShellCore_WebAppStarted, $"CloudExperienceHost Web App Activity started. CXID: '{longCxid}'.", lastPage: null);
+
+            Assert.NotNull(crumb);
+            Assert.True(crumb!.Length < 200, crumb);
+            Assert.EndsWith("…", crumb);
+        }
+
+        [Theory]
+        [InlineData("OobeNDUP", true)]
+        [InlineData("RebootNDUP", true)]
+        [InlineData("EarlyRebootNDUP", true)]
+        [InlineData("ExpeditedUpdate_startWUScanStarted", true)]
+        [InlineData("AADHello", false)]
+        [InlineData("MDMProgressAfterAADRefactored", false)]
+        [InlineData(null, false)]
+        public void UpdatePageTokens_AreRecognized(string? token, bool expected)
+        {
+            Assert.Equal(expected, ShellCoreTracker.IsUpdatePageToken(token!));
+        }
+
+        // ------------------------------------------------------ update page records ----
+
+        [Fact]
+        public void UpdatePageRecords_ArePageStartsStopsAndNames_OfTheUpdatePageOnly()
+        {
+            var start = ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, lastPage: null);
+            Assert.Equal(OobeUpdateVocabulary.PageStarted, start!.CxhEvent);
+            Assert.Equal("OobeNDUP", start.Page);
+
+            var stop = ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, lastPage: "RebootNDUP");
+            Assert.Equal(OobeUpdateVocabulary.PageStopped, stop!.CxhEvent);
+            Assert.Equal("RebootNDUP", stop.Page);
+            Assert.Equal("success", stop.Result);
+
+            var name = ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, lastPage: null);
+            Assert.Equal(OobeUpdateVocabulary.EventName, name!.CxhEvent);
+            Assert.Equal("ExpeditedUpdate_startWUScanStarted", name.Name);
+            Assert.Null(name.Value);
+
+            // Other pages and names are no update-page records.
+            Assert.Null(ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppStarted, EspPageStarted, lastPage: null));
+            Assert.Null(ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, lastPage: "MDMProgressAfterAADRefactored"));
+            Assert.Null(ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppEvent, NavigateWithTenantUrl, lastPage: "OobeNDUP"));
+        }
+
+        [Fact]
+        public void UpdatePageRecord_CarriesOnlyASafeValue()
+        {
+            var unsafeValue = ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppEvent, DownloadSucceededWithValue, lastPage: null);
+            Assert.Null(unsafeValue!.Value);
+
+            var gate = ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppEvent, CspGateTrue, lastPage: null);
+            Assert.Equal("true", gate!.Value);
+        }
+
+        [Theory]
+        [InlineData("true", "true")]
+        [InlineData("FALSE", "FALSE")]
+        [InlineData("0", "0")]
+        [InlineData("-2147024891", "-2147024891")]
+        [InlineData("0x80240022", "0x80240022")]
+        [InlineData("12345678901", null)]          // more than ten digits
+        [InlineData("0x123456789", null)]          // more than eight hex digits
+        [InlineData("https://login.microsoftonline.com/x", null)]
+        [InlineData("{\"result\":0}", null)]
+        [InlineData("true and more", null)]
+        [InlineData("", null)]
+        public void SafeValues_AreBooleansIntegersAndHresults(string value, string? expected)
+        {
+            var description = $"CloudExperienceHost Web App Event 2. Name: 'ExpeditedUpdate_x', Value: '{value}'.";
+
+            Assert.Equal(expected, ShellCoreTracker.ExtractSafeValue(description));
+        }
+
+        [Fact]
+        public void LiveUpdatePage_IsReported_WithTheRegistryState_AndRaisesNothing()
+        {
+            _registry = new[] { NdupKey("EnableExpeditedUpdate=1") };
+            using var tracker = Build();
+            var raised = 0;
+            tracker.EspExited += (_, _) => raised++;
+            tracker.EspFailureDetected += (_, _) => raised++;
+            tracker.FinalizingSetupPhaseTriggered += (_, _) => raised++;
+
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, "Microsoft-Windows-Shell-Core", isBackfill: false);
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, At.AddMinutes(1), "Microsoft-Windows-Shell-Core", isBackfill: false);
+            _registry = new[] { NdupKey("EnableExpeditedUpdate=1, EnableExpeditedUpdateSyncInstallCompleted=1") };
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(30), "Microsoft-Windows-Shell-Core", isBackfill: false);
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage);
+            Assert.Equal(new object[] { "page_started", "event_name", "page_stopped" }, pages.Select(p => Data(p)["cxhEvent"]).ToArray());
+            Assert.All(pages, p => Assert.Equal(false, Data(p)["backfill"]));
+
+            var states = ByType(Constants.EventTypes.OobeUpdateState);
+            Assert.Equal(new object[] { "update_page_started", "update_page_stopped" }, states.Select(s => Data(s)["moment"]).ToArray());
+            Assert.All(states, s => Assert.Equal("OobeNDUP", Data(s)["page"]));
+
+            // Telemetry only — no ESP signal, no other event.
+            Assert.Equal(0, raised);
+            Assert.False(tracker.IsEspExitedForTest);
+            Assert.Equal(pages.Count + states.Count, _sink.Posted.Count);
+        }
+
+        [Fact]
+        public void OtherPages_AreNotReported()
+        {
+            _registry = new[] { NdupKey("EnableExpeditedUpdate=1") };
+            using var tracker = Build();
+
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppStarted, EspPageStarted, At, "Microsoft-Windows-Shell-Core", isBackfill: false);
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(1), "Microsoft-Windows-Shell-Core", isBackfill: false);
+
+            Assert.Empty(_sink.Posted);
+        }
+
+        [Fact]
+        public void Backfill_ReportsTheUpdatePage_WithItsEventTimes_ButReadsNoRegistry()
+        {
+            // The registry shows the state now, not at the record's time.
+            var reads = 0;
+            using var tracker = new ShellCoreTracker("S1", "T1",
+                new InformationalEventPost(_sink, new VirtualClock(At)),
+                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                helloTracker: null,
+                oobeUpdateRegistryReader: () => { reads++; return new[] { NdupKey("EnableExpeditedUpdate=1") }; });
+
+            tracker.ReplayBackfillRecords(new[]
+            {
+                (ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(-4)),
+                (ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, At.AddMinutes(-3)),
+                (ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(-2)),
+            });
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage);
+            Assert.Equal(3, pages.Count);
+            Assert.All(pages, p => Assert.Equal(true, Data(p)["backfill"]));
+            Assert.Equal(At.AddMinutes(-4), pages[0].OccurredAtUtc);
+            Assert.Equal(0, reads);
+            // Nothing else: no ESP exit or failure was in the window, so no skipped-records trace.
+            Assert.Equal(3, _sink.Posted.Count);
+        }
+
+        // ------------------------------------------------------------ localization ----
+
+        [Fact]
+        public void LocalizedRecords_AreReadFromTheirProperties()
+        {
+            using var tracker = Build();
+
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppStarted, FrenchNdupStarted, At, "Microsoft-Windows-Shell-Core",
+                isBackfill: false, properties: new[] { "OobeNDUP" });
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppEvent, FrenchCspGate, At.AddSeconds(5), "Microsoft-Windows-Shell-Core",
+                isBackfill: false, properties: new[] { "ExpeditedUpdate_isNDUPAllowedByCSPSucceeded", "true" });
+            tracker.ProcessEvent(ShellCoreTracker.EventId_ShellCore_WebAppStopped, FrenchPageStopped, At.AddMinutes(1), "Microsoft-Windows-Shell-Core",
+                isBackfill: false, properties: new[] { "success" });
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage).Select(Data).ToList();
+            Assert.Equal(new object[] { "page_started", "event_name", "page_stopped" }, pages.Select(d => d["cxhEvent"]).ToArray());
+            Assert.Equal("OobeNDUP", pages[0]["page"]);
+            Assert.Equal("ExpeditedUpdate_isNDUPAllowedByCSPSucceeded", pages[1]["name"]);
+            Assert.Equal("true", pages[1]["value"]);
+            Assert.Equal("OobeNDUP", pages[2]["page"]);
+            Assert.Equal("success", pages[2]["result"]);
+        }
+
+        [Fact]
+        public void LocalizedMessage_WithoutProperties_DoesNotYieldItsLabelledFields()
+        {
+            // Why the properties are read: the French labels are not the manifest's.
+            Assert.Null(ShellCoreTracker.ReadCxhFields(ShellCoreTracker.EventId_ShellCore_WebAppStopped, FrenchPageStopped, properties: null).Primary);
+            Assert.Null(ShellCoreTracker.ReadCxhFields(ShellCoreTracker.EventId_ShellCore_WebAppEvent, FrenchCspGate, properties: null).Primary);
+
+            Assert.Equal("success",
+                ShellCoreTracker.ReadCxhFields(ShellCoreTracker.EventId_ShellCore_WebAppStopped, FrenchPageStopped, new[] { "success" }).Primary);
+        }
+
+        [Theory]
+        [InlineData("CloudExperienceHost Web App Event 2. Name: 'ExpeditedUpdate_x', Value: 'true'.")]
+        [InlineData("CloudExperienceHost Web App Event 2. Name : « ExpeditedUpdate_x », Value : « true ».")]
+        [InlineData("CloudExperienceHost Web App Event 2. Name\u00A0: «\u202FExpeditedUpdate_x\u202F», Value\u00A0: «\u00A0true\u00A0».")]
+        public void MessageFallback_AcceptsQuotesAndGuillemets(string description)
+        {
+            var fields = ShellCoreTracker.ReadCxhFields(ShellCoreTracker.EventId_ShellCore_WebAppEvent, description, properties: null);
+
+            Assert.Equal("ExpeditedUpdate_x", fields.Primary);
+            Assert.Equal("true", fields.Value);
+        }
+
+        [Fact]
+        public void PropertyValue_LeavesTheTrackerOnlyInASafeForm()
+        {
+            var fields = ShellCoreTracker.ReadCxhFields(ShellCoreTracker.EventId_ShellCore_WebAppEvent, "",
+                new[] { "ExpeditedUpdate_commitExpeditionDownloadInstallAsyncSucceeded", "{\"url\":\"https://login.microsoftonline.com/x\"}" });
+
+            var record = ShellCoreTracker.ParseUpdatePageRecord(ShellCoreTracker.EventId_ShellCore_WebAppEvent, fields, lastPage: null);
+            Assert.Equal("ExpeditedUpdate_commitExpeditionDownloadInstallAsyncSucceeded", record!.Name);
+            Assert.Null(record.Value);
+            Assert.DoesNotContain("microsoftonline",
+                ShellCoreTracker.FormatCxhBreadcrumb(ShellCoreTracker.EventId_ShellCore_WebAppEvent, fields, lastPage: null));
+        }
+
+        // ------------------------------------------------------- restart watermark ----
+
+        [Fact]
+        public void RestartBackfill_SkipsUpdatePageRecords_AnEarlierRunReported()
+        {
+            using (var first = Build(StateDirectory))
+            {
+                Live(first, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, recordId: 500);
+                Live(first, ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, At.AddMinutes(1), recordId: 501);
+            }
+
+            // The restart reads the minutes before it again — plus the stop the first run missed.
+            using var second = Build(StateDirectory);
+            second.LoadPageWatermark();
+            second.ReplayBackfillRecords(new[]
+            {
+                new ShellCoreRecord(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, recordId: 500),
+                new ShellCoreRecord(ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, At.AddMinutes(1), recordId: 501),
+                new ShellCoreRecord(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(2), recordId: 502),
+            });
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage).Select(Data).ToList();
+            Assert.Equal(new object[] { "page_started", "event_name", "page_stopped" }, pages.Select(d => d["cxhEvent"]).ToArray());
+            Assert.Equal(new object[] { false, false, true }, pages.Select(d => d["backfill"]).ToArray());
+            // The skipped start still names the page the stop belongs to.
+            Assert.Equal("OobeNDUP", pages[2]["page"]);
+        }
+
+        [Fact]
+        public void SameRecord_FromTheLiveWatcherAndTheBackfill_IsReportedOnce()
+        {
+            // The live watcher is armed before the backfill runs, so both can deliver a record.
+            using var tracker = Build(StateDirectory);
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, recordId: 700);
+            tracker.ReplayBackfillRecords(new[]
+            {
+                new ShellCoreRecord(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, recordId: 700),
+            });
+
+            Assert.Single(ByType(Constants.EventTypes.OobeUpdatePage));
+        }
+
+        [Fact]
+        public void Watermark_FollowsReportedRecordsOnly()
+        {
+            using var tracker = Build(StateDirectory);
+            for (var i = 0; i <= OobeUpdateTelemetry.MaxPageEventsPerKey; i++)
+                Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppEventName, ScanStartedName, At.AddSeconds(i), recordId: 800 + i);
+
+            // The repeat over the per-name cap is claimed for this run, not written down.
+            Assert.Equal(OobeUpdateTelemetry.MaxPageEventsPerKey, ByType(Constants.EventTypes.OobeUpdatePage).Count);
+            var state = JsonConvert.DeserializeObject<EventRecordWatermark.WatermarkState>(
+                File.ReadAllText(Path.Combine(StateDirectory, ShellCoreTracker.PageWatermarkStateFileName)));
+            Assert.Equal(800 + OobeUpdateTelemetry.MaxPageEventsPerKey - 1, state!.LastRecordId);
+        }
+
+        [Fact]
+        public void RecordsWithoutARecordId_AreNotDeduplicated()
+        {
+            using var tracker = Build(StateDirectory);
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, recordId: -1);
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(5), recordId: -1);
+
+            Assert.Equal(2, ByType(Constants.EventTypes.OobeUpdatePage).Count);
+            Assert.False(File.Exists(Path.Combine(StateDirectory, ShellCoreTracker.PageWatermarkStateFileName)));
+        }
+
+        [Fact]
+        public void AgentStartAndStop_ReportTheRegistryState_StopOnce()
+        {
+            _registry = new[] { NdupKey("EnableExpeditedUpdate=1") };
+            var tracker = Build();
+
+            tracker.Start();
+            _registry = new[] { NdupKey("EnableExpeditedUpdate=1, ExpeditedUpdateStatus=2") };
+            tracker.Stop();
+            tracker.Stop();
+            tracker.Dispose();
+
+            var states = ByType(Constants.EventTypes.OobeUpdateState);
+            Assert.Equal(new object[] { "agent_start", "agent_stop" }, states.Select(s => Data(s)["moment"]).ToArray());
+        }
+
+        [Fact]
+        public void TrackerThatNeverStarted_ReportsNothingAtStop()
+        {
+            _registry = new[] { NdupKey("EnableExpeditedUpdate=1") };
+            var tracker = Build();
+
+            tracker.Dispose();
+
+            Assert.Empty(_sink.Posted);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/ShellCoreTrackerHelloWizardTests.cs

@@ -84,6 +84,55 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
             Assert.False(raised);
         }
 
+        [Fact]
+        public void ProcessEvent_62404_NGC_in_a_localized_message_is_read_from_the_cxid_property()
+        {
+            // A French Windows quotes the CXID in guillemets — the "'NGC'" substring never matched.
+            using var tmp = new TempDirectory();
+            using var tracker = MakeTracker(tmp, new VirtualClock(ClockNow));
+            var raised = 0;
+            tracker.HelloWizardStarted += (_, _) => raised++;
+
+            tracker.ProcessEvent(
+                eventId: ShellCoreTracker.EventId_ShellCore_WebAppStarted,
+                description: "Activité d’application web CloudExperienceHost démarrée. CXID : « NGC ».",
+                timestamp: ClockNow,
+                providerName: "Microsoft-Windows-Shell-Core",
+                isBackfill: false,
+                properties: new[] { "NGC" });
+
+            Assert.Equal(1, raised);
+        }
+
+        [Theory]
+        [InlineData("AADHello", true)]
+        [InlineData("NGC", true)]
+        [InlineData("NGCPin", false)]
+        [InlineData("OobeNDUP", false)]
+        public void HelloWizardStart_is_decided_by_the_cxid(string cxid, bool expected)
+        {
+            Assert.Equal(expected, ShellCoreTracker.IsHelloWizardStart(cxid, description: "CXID: 'AADHello'"));
+        }
+
+        [Fact]
+        public void Backfill_62404_reads_the_cxid_property()
+        {
+            using var tmp = new TempDirectory();
+            using var tracker = MakeTracker(tmp, new VirtualClock(ClockNow));
+            var captured = new List<HelloWizardStartedEventArgs>();
+            tracker.HelloWizardStarted += (_, args) => captured.Add(args);
+
+            var historical = ClockNow.AddMinutes(-3);
+            tracker.ReplayBackfillRecords(new[]
+            {
+                new ShellCoreRecord(ShellCoreTracker.EventId_ShellCore_WebAppStarted,
+                    "Activité d’application web CloudExperienceHost démarrée. CXID : « NGC ».", historical,
+                    recordId: 42, properties: new[] { "NGC" }),
+            });
+
+            Assert.Equal(historical, Assert.Single(captured).OccurredAtUtc);
+        }
+
         [Fact]
         public void Backfill_62404_raises_once_with_historical_timestamp()
         {

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/ShellCoreTrackerUpdatePageBackfillTests.cs

@@ -0,0 +1,225 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.Shared;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring
+{
+    /// <summary>
+    /// The first run's update page backfill (<see cref="ShellCoreTracker.BackfillUpdatePageTelemetry"/>)
+    /// and the page a stop belongs to across backfill and live records. The first run has no
+    /// replay — its backfill is telemetry and nothing else, so a Hello-wizard start, an ESP exit
+    /// or an ESP failure in the window must not leave the tracker on any rail.
+    /// </summary>
+    public sealed class ShellCoreTrackerUpdatePageBackfillTests : IDisposable
+    {
+        private static readonly DateTime At = new DateTime(2026, 10, 5, 13, 10, 0, DateTimeKind.Utc);
+
+        private const string NdupStarted = "CloudExperienceHost Web App Activity started. CXID: 'OobeNDUP'.";
+        private const string RebootNdupStarted = "CloudExperienceHost Web App Activity started. CXID: 'RebootNDUP'.";
+        private const string AadHelloStarted = "CloudExperienceHost Web App Activity started. CXID: 'AADHello'.";
+        private const string PageStopped = "CloudExperienceHost Web App Activity stopped. Result: 'success'.";
+        private const string DownloadSucceeded =
+            "CloudExperienceHost Web App Event 1. Name: 'SdxWebAppCloudNDUP_processStatusChangeFromHandler_downloadSucceeded'.";
+        private const string EspExit = "CommercialOOBE_ESPProgress_Page_Exiting";
+        private const string EspFailure = "CommercialOOBE_ESPProgress_Failure";
+        private const string WhiteGloveSuccess = "CommercialOOBE_ESPProgress_WhiteGlove_Success";
+
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly FakeSignalIngressSink _sink = new FakeSignalIngressSink();
+        private int _registryReads;
+
+        public void Dispose() => _tmp.Dispose();
+
+        private ShellCoreTracker Build() =>
+            new ShellCoreTracker("S1", "T1",
+                new InformationalEventPost(_sink, new VirtualClock(At)),
+                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                helloTracker: null,
+                oobeUpdateRegistryReader: () => { _registryReads++; return Array.Empty<OobeUpdateRegistrySnapshot.KeyState>(); },
+                stateDirectory: Path.Combine(_tmp.Path, "state"));
+
+        private static void Live(ShellCoreTracker tracker, int eventId, string description, DateTime at, long recordId) =>
+            tracker.ProcessEvent(eventId, description, at, "Microsoft-Windows-Shell-Core", isBackfill: false, recordId: recordId);
+
+        private static ShellCoreRecord Record(int eventId, string description, DateTime at, long recordId) =>
+            new ShellCoreRecord(eventId, description, at, recordId);
+
+        private IReadOnlyList<IReadOnlyDictionary<string, object>> Pages() =>
+            _sink.Posted
+                .Where(p => p.Kind == DecisionSignalKind.InformationalEvent
+                    && p.Payload != null
+                    && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                    && et == Constants.EventTypes.OobeUpdatePage)
+                .Select(p => (IReadOnlyDictionary<string, object>)p.TypedPayload!)
+                .ToList();
+
+        // ------------------------------------------------------------ first run ----
+
+        [Fact]
+        public void FirstRunBackfill_ReportsTheUpdatePage_AndNothingElse()
+        {
+            using var tracker = Build();
+            var raised = new List<string>();
+            tracker.HelloWizardStarted += (_, _) => raised.Add("hello");
+            tracker.FinalizingSetupPhaseTriggered += (_, reason) => raised.Add($"finalizing:{reason}");
+            tracker.EspExited += (_, _) => raised.Add("exit");
+            tracker.EspFailureDetected += (_, _) => raised.Add("failure");
+            tracker.WhiteGloveCompleted += (_, _) => raised.Add("whiteglove");
+
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppEvent, EspExit, At.AddMinutes(-41), 95),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppEvent, EspFailure, At.AddSeconds(-2430), 96),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppEvent, WhiteGloveSuccess, At.AddSeconds(-2420), 97),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(-40), 100),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppEventName, DownloadSucceeded, At.AddMinutes(-30), 101),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, AadHelloStarted, At.AddMinutes(-2), 110),
+            });
+
+            Assert.Empty(raised);
+            Assert.False(tracker.IsEspExitedForTest);
+            Assert.False(tracker.IsWhiteGloveDetectedForTest);
+            var pages = Pages();
+            Assert.Equal(new object[] { "page_started", "event_name" }, pages.Select(d => d["cxhEvent"]).ToArray());
+            Assert.All(pages, d => Assert.Equal(true, d["backfill"]));
+            // No agent_trace, no ESP or Hello event — only the two page rows.
+            Assert.Equal(2, _sink.Posted.Count);
+            // The registry shows the state now, not at the records' time.
+            Assert.Equal(0, _registryReads);
+        }
+
+        [Fact]
+        public void FirstRunBackfill_KeepsTheEventTimes()
+        {
+            using var tracker = Build();
+
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(-40), 100),
+            });
+
+            var posted = Assert.Single(_sink.Posted);
+            Assert.Equal(At.AddMinutes(-40), posted.OccurredAtUtc);
+        }
+
+        [Fact]
+        public void LiveStop_FindsThePageThatStartedBeforeTheAgent()
+        {
+            using var tracker = Build();
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(-40), 100),
+            });
+
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(5), 120);
+
+            var stop = Pages().Last();
+            Assert.Equal("page_stopped", stop["cxhEvent"]);
+            Assert.Equal("OobeNDUP", stop["page"]);
+            Assert.Equal(false, stop["backfill"]);
+        }
+
+        [Fact]
+        public void SameRecord_FromTheLiveWatcherAndTheFirstRunBackfill_IsReportedOnce()
+        {
+            // The live watcher is armed before the backfill reads, so both can deliver a record.
+            using var tracker = Build();
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, 700);
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, 700),
+            });
+
+            Assert.Single(Pages(), d => (string)d["cxhEvent"] == "page_started");
+        }
+
+        // ---------------------------------------------------- the page of a stop ----
+
+        [Fact]
+        public void ReplayedOlderStart_DoesNotTakeOverTheNextLiveStop()
+        {
+            // A restart replay reads records older than the live watcher's; before, its page start
+            // overwrote the live page and the next live stop was attributed to the old page.
+            using var tracker = Build();
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, RebootNdupStarted, At, 900);
+            tracker.ReplayBackfillRecords(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(-20), 850),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppEventName, DownloadSucceeded, At.AddMinutes(-19), 851),
+            });
+
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(1), 901);
+
+            var stop = Pages().Last();
+            Assert.Equal("page_stopped", stop["cxhEvent"]);
+            Assert.Equal("RebootNDUP", stop["page"]);
+        }
+
+        [Fact]
+        public void BackfilledStop_BelongsToTheStartOfItsOwnBatch()
+        {
+            using var tracker = Build();
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, RebootNdupStarted, At, 900);
+
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At.AddMinutes(-20), 850),
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(-18), 852),
+            });
+
+            var stop = Pages().Last();
+            Assert.Equal("page_stopped", stop["cxhEvent"]);
+            Assert.Equal("OobeNDUP", stop["page"]);
+            Assert.Equal(true, stop["backfill"]);
+        }
+
+        [Fact]
+        public void BackfilledStopWithoutItsStart_IsNotGivenTheLivePage()
+        {
+            using var tracker = Build();
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, 900);
+
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(-18), 852),
+            });
+
+            Assert.DoesNotContain(Pages(), d => (string)d["cxhEvent"] == "page_stopped");
+        }
+
+        [Fact]
+        public void NewerBackfilledStart_MovesTheLivePageForward()
+        {
+            // Records written between arming the watcher and the backfill's read are newer than
+            // the last live start the watcher delivered before them.
+            using var tracker = Build();
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStarted, NdupStarted, At, 900);
+            tracker.ReplayUpdatePageTelemetry(new[]
+            {
+                Record(ShellCoreTracker.EventId_ShellCore_WebAppStarted, RebootNdupStarted, At.AddSeconds(30), 905),
+            });
+
+            Live(tracker, ShellCoreTracker.EventId_ShellCore_WebAppStopped, PageStopped, At.AddMinutes(1), 906);
+
+            Assert.Equal("RebootNDUP", Pages().Last()["page"]);
+        }
+
+        [Fact]
+        public void UpdatePageLookback_IsInsideTheReplayClamp()
+        {
+            Assert.Equal(ShellCoreTracker.UpdatePageBackfillLookbackMinutes,
+                ShellCoreTracker.ClampLookbackMinutes(ShellCoreTracker.UpdatePageBackfillLookbackMinutes));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/ImeRegistryAppStateObserverTests.cs

@@ -59,9 +59,17 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
         public void ClassifyEnforcementState_bands(int state, string expected)
             => Assert.Equal(expected, ImeRegistryAppStateObserver.ClassifyEnforcementState(state));
 
+        // IME AppInstallStatus values (StatusServiceReports\..\Status), stable IME 1.50 .. 1.106.
+        // 1001/1003 sit inside the 1000 band but are NOT terminal — IME maps every InProgress
+        // enforcement state to 1001 (verified against IME 1.106).
         [Theory]
         [InlineData(1000, "installed")]
-        [InlineData(1999, "installed")]
+        [InlineData(1002, "installed")]
+        [InlineData(1004, "installed")]
+        [InlineData(1001, "installing")]
+        [InlineData(1003, "installing")]
+        [InlineData(1005, null)]
+        [InlineData(1999, null)]
         [InlineData(3000, "failed")]
         [InlineData(2000, "notApplicable")]
         [InlineData(2999, "notApplicable")]
@@ -72,6 +80,35 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
         public void ClassifyStatusServiceStatus_bands(int status, string? expected)
             => Assert.Equal(expected, ImeRegistryAppStateObserver.ClassifyStatusServiceStatus(status));
 
+        [Fact]
+        public void TryParseRegistryDateTime_reads_both_ime_shapes_as_utc()
+        {
+            // ExecutionDeadlineTime: DateTime.ToString(InvariantCulture), UTC without a kind marker.
+            var deadline = ImeRegistryAppStateObserver.TryParseRegistryDateTime("09/23/2026 18:00:00");
+            Assert.Equal(new DateTime(2026, 9, 23, 18, 0, 0, DateTimeKind.Utc), deadline);
+            Assert.Equal(DateTimeKind.Utc, deadline!.Value.Kind);
+
+            // DeferUntilTime: round-trip "o" with trailing Z.
+            var until = ImeRegistryAppStateObserver.TryParseRegistryDateTime("2026-09-23T10:30:00.0000000Z");
+            Assert.Equal(new DateTime(2026, 9, 23, 10, 30, 0, DateTimeKind.Utc), until);
+            Assert.Equal(DateTimeKind.Utc, until!.Value.Kind);
+
+            Assert.Null(ImeRegistryAppStateObserver.TryParseRegistryDateTime(null));
+            Assert.Null(ImeRegistryAppStateObserver.TryParseRegistryDateTime(""));
+            Assert.Null(ImeRegistryAppStateObserver.TryParseRegistryDateTime("not a date"));
+            Assert.Null(ImeRegistryAppStateObserver.TryParseRegistryDateTime(42));
+        }
+
+        [Fact]
+        public void TryReadBool_parses_registry_strings_only()
+        {
+            Assert.True(ImeRegistryAppStateObserver.TryReadBool("True"));
+            Assert.False(ImeRegistryAppStateObserver.TryReadBool("false"));
+            Assert.Null(ImeRegistryAppStateObserver.TryReadBool("yes"));
+            Assert.Null(ImeRegistryAppStateObserver.TryReadBool(1));
+            Assert.Null(ImeRegistryAppStateObserver.TryReadBool(null));
+        }
+
         [Fact]
         public void TerminalOutcome_prefers_enforcement_state_then_status_service()
         {
@@ -88,6 +125,49 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             Assert.Null(ImeRegistryAppStateObserver.TerminalOutcome(Entry(enforcementState: 3000)));
             Assert.Null(ImeRegistryAppStateObserver.TerminalOutcome(Entry(statusServiceStatus: 2500)));
             Assert.Null(ImeRegistryAppStateObserver.TerminalOutcome(Entry()));
+            // Installing (1001) / InstallingPendingReboot (1003) share the 1000 band but are not terminal.
+            Assert.Null(ImeRegistryAppStateObserver.TerminalOutcome(Entry(statusServiceStatus: 1001)));
+            Assert.Null(ImeRegistryAppStateObserver.TerminalOutcome(Entry(enforcementState: 2009, statusServiceStatus: 1003)));
+        }
+
+        [Fact]
+        public void ChangedFields_reports_wait_state_triggers_only()
+        {
+            var prev = Entry(enforcementState: 2009);
+            var next = Entry(enforcementState: 2009,
+                installDeadlineUtc: T0.AddHours(2),
+                deferralsUsed: 1, deferralMaxDeferrals: 3, deferUntilUtc: T0.AddMinutes(30), deferralAutoDeferred: false);
+
+            Assert.Equal(new[] { "installDeadline", "deferralsUsed", "deferUntil" },
+                ImeRegistryAppStateObserver.ChangedFields(prev, next));
+
+            // MaxDeferrals / AutoDeferred alone are data, not a transition.
+            var sameCounters = Entry(enforcementState: 2009,
+                installDeadlineUtc: T0.AddHours(2),
+                deferralsUsed: 1, deferralMaxDeferrals: 5, deferUntilUtc: T0.AddMinutes(30), deferralAutoDeferred: true);
+            Assert.Empty(ImeRegistryAppStateObserver.ChangedFields(next, sameCounters));
+
+            // A cleared deadline is a transition too (IME clears it when the next download starts).
+            Assert.Equal(new[] { "installDeadline" },
+                ImeRegistryAppStateObserver.ChangedFields(
+                    Entry(installDeadlineUtc: T0.AddHours(2)), Entry()));
+        }
+
+        [Fact]
+        public void DescribeWaitState_texts()
+        {
+            Assert.Equal(string.Empty, ImeRegistryAppStateObserver.DescribeWaitState(Entry(enforcementState: 2009)));
+            Assert.Equal(", downloaded, install deadline 2026-08-18 10:00 UTC",
+                ImeRegistryAppStateObserver.DescribeWaitState(Entry(installDeadlineUtc: T0.AddHours(2))));
+            Assert.Equal(", deferred by user 1/3 until 2026-08-18 08:30 UTC",
+                ImeRegistryAppStateObserver.DescribeWaitState(Entry(
+                    deferralsUsed: 1, deferralMaxDeferrals: 3, deferUntilUtc: T0.AddMinutes(30), deferralAutoDeferred: false)));
+            Assert.Equal(", auto-deferred 2/3",
+                ImeRegistryAppStateObserver.DescribeWaitState(Entry(
+                    deferralsUsed: 2, deferralMaxDeferrals: 3, deferralAutoDeferred: true)));
+            // Zero deferrals used is not a deferral; a missing max falls back to the bare count.
+            Assert.Equal(string.Empty, ImeRegistryAppStateObserver.DescribeWaitState(Entry(deferralsUsed: 0, deferralMaxDeferrals: 3)));
+            Assert.Equal(", deferred by user 1", ImeRegistryAppStateObserver.DescribeWaitState(Entry(deferralsUsed: 1)));
         }
 
         [Fact]
@@ -184,6 +264,54 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             Assert.Equal("success", evt.Payload["enforcementClass"]);
         }
 
+        [Fact]
+        public void Wait_state_changes_emit_state_events_with_data_and_text()
+        {
+            var (sink, clock, observer) = CreateObserver(trackerApps: null);
+            var current = Snapshot((App1, 2009, null));
+
+            using (new ImeRegistryAppStateObserver.ScopedSnapshotOverride(() => current))
+            {
+                observer.Tick("baseline");
+
+                // Download finished, IME parks the app until its install deadline (1.106 ExecutionDeadlineTime).
+                var withDeadline = Snapshot((App1, 2009, null));
+                withDeadline.Entries.Values.Single().InstallDeadlineUtc = T0.AddHours(2);
+                current = withDeadline;
+                observer.Tick("registry_change");
+
+                // A required app hits a running process and the user defers (1.105 app-in-use deferral).
+                var deferred = Snapshot((App1, 2014, null));
+                var entry = deferred.Entries.Values.Single();
+                entry.InstallDeadlineUtc = T0.AddHours(2);
+                entry.DeferralsUsed = 1;
+                entry.DeferralMaxDeferrals = 3;
+                entry.DeferUntilUtc = T0.AddMinutes(30);
+                entry.DeferralAutoDeferred = false;
+                current = deferred;
+                observer.Tick("registry_change");
+            }
+
+            var events = Events(sink, SharedEventTypes.RegistryAppState);
+            Assert.Equal(2, events.Count);
+
+            var deadlineEvent = events[0];
+            Assert.Equal("installDeadline", deadlineEvent.Payload!["changedFields"]);
+            Assert.Equal("2026-08-18T10:00:00.0000000Z", deadlineEvent.Payload["installDeadlineUtc"]);
+            Assert.DoesNotContain("deferralsUsed", deadlineEvent.Payload.Keys);
+            Assert.Contains("-> inProgress, downloaded, install deadline 2026-08-18 10:00 UTC",
+                deadlineEvent.Payload[SignalPayloadKeys.Message]);
+
+            var deferralEvent = events[1];
+            Assert.Equal("enforcementState,deferralsUsed,deferUntil", deferralEvent.Payload!["changedFields"]);
+            Assert.Equal("2014", deferralEvent.Payload["enforcementState"]);
+            Assert.Equal("1", deferralEvent.Payload["deferralsUsed"]);
+            Assert.Equal("3", deferralEvent.Payload["deferralMaxDeferrals"]);
+            Assert.Equal("2026-08-18T08:30:00.0000000Z", deferralEvent.Payload["deferUntilUtc"]);
+            Assert.Equal("false", deferralEvent.Payload["deferralAutoDeferred"]);
+            Assert.Contains("deferred by user 1/3 until 2026-08-18 08:30 UTC", deferralEvent.Payload[SignalPayloadKeys.Message]);
+        }
+
         [Fact]
         public void NonEmpty_baseline_emits_one_summary_with_counts()
         {
@@ -331,7 +459,9 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
 
         private static AppRegistryEntry Entry(
             int? enforcementState = null, long? errorCode = null, int? exitCode = null,
-            int? statusServiceStatus = null, bool espTracked = false, string? espPhase = null)
+            int? statusServiceStatus = null, bool espTracked = false, string? espPhase = null,
+            DateTime? installDeadlineUtc = null, int? deferralsUsed = null, int? deferralMaxDeferrals = null,
+            DateTime? deferUntilUtc = null, bool? deferralAutoDeferred = null)
         {
             var entry = new AppRegistryEntry($"{ImeRegistrySnapshot.DeviceContext}|{App1}", ImeRegistrySnapshot.DeviceContext, App1);
             entry.EnforcementState = enforcementState;
@@ -340,6 +470,11 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             entry.StatusServiceStatus = statusServiceStatus;
             entry.EspTracked = espTracked;
             entry.EspPhase = espPhase;
+            entry.InstallDeadlineUtc = installDeadlineUtc;
+            entry.DeferralsUsed = deferralsUsed;
+            entry.DeferralMaxDeferrals = deferralMaxDeferrals;
+            entry.DeferUntilUtc = deferUntilUtc;
+            entry.DeferralAutoDeferred = deferralAutoDeferred;
             return entry;
         }
 

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/ImeRegistryScriptResultObserverTests.cs

@@ -0,0 +1,411 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.Ime;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using Xunit;
+using SharedEventTypes = AutopilotMonitor.Shared.Constants.EventTypes;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// D-316: IME saves every platform script's result under Policies\&lt;user&gt;\&lt;policy&gt; after reporting the
+    /// batch; the observer checks the tracker's emitted run against it. The field case (session 756970cf): the run
+    /// had been given a Win32 detection script's end block — exit 1 and "Detection Started" output — while IME saved
+    /// the bootstrap output of the platform script itself.
+    /// </summary>
+    public sealed class ImeRegistryScriptResultObserverTests
+    {
+        private const string DeviceUser = "00000000-0000-0000-0000-000000000000";
+        private const string PolicyA = "1d6f0a52-3c4e-4b7a-9e21-5f8c7d2b9a10";
+        private const string PolicyB = "2b7d9e41-8c3a-4f60-a5d2-9e1b7c4f3a08";
+        private const string OwnStdout = "=== bootstrap loader started ===\nInstaller finished (exit code 0).";
+        private const string ForeignStdout = "VERBOSE: === Sample Suite Detection Started ===\nWARNING: === DETECTION FAILED ===";
+        private static readonly DateTime T0 = new DateTime(2026, 10, 3, 20, 59, 0, DateTimeKind.Utc);
+
+        // ── PlatformOutputJudge ─────────────────────────────────────────────────
+
+        private static PlatformScriptRun Run(string? stdout, string? stderr = null, int? exitCode = 0, string result = "Success", string resultSource = "ime_policy_result")
+            => new PlatformScriptRun { PolicyId = PolicyA, UserId = DeviceUser, RunId = "run-1", Emitted = true, Result = result, ResultSource = resultSource, ExitCode = exitCode, Stdout = stdout, Stderr = stderr };
+
+        private static string Details(string executionMessage)
+            => "{\"Version\":1,\"SigningCode\":15,\"EncryptionCode\":19,\"ExecutionMsg\":" + System.Text.Json.JsonSerializer.Serialize(executionMessage) + "}";
+
+        private static SavedScriptResult Saved(string? executionMessage, string result = "Success", int errorCode = 0, string user = DeviceUser, string policy = PolicyA, string stamp = "10/3/2026 9:00:00 PM")
+            => new SavedScriptResult
+            {
+                UserId = user,
+                PolicyId = policy,
+                Result = result,
+                ErrorCode = errorCode,
+                ResultDetails = executionMessage == null ? null : Details(executionMessage),
+                LastUpdatedTimeUtc = stamp,
+            };
+
+        [Fact]
+        public void Field_case_detection_output_on_the_platform_run_is_foreign_and_the_saved_stdout_replaces_it()
+        {
+            var judgement = PlatformOutputJudge.Judge(Run(ForeignStdout, string.Empty, exitCode: 1), Saved(OwnStdout.Replace("\n", "\r\n")));
+            Assert.Equal(PlatformOutputVerdict.Foreign, judgement.Verdict);
+            Assert.Equal("stdout_differs", judgement.Reason);
+            Assert.Equal(OwnStdout, judgement.Stdout);
+            Assert.Equal(string.Empty, judgement.Stderr);
+        }
+
+        [Fact]
+        public void Matching_output_is_verified_across_line_ending_and_trim_differences()
+        {
+            var judgement = PlatformOutputJudge.Judge(Run(OwnStdout, string.Empty), Saved("  " + OwnStdout.Replace("\n", "\r\n") + "\r\n"));
+            Assert.Equal(PlatformOutputVerdict.Verified, judgement.Verdict);
+        }
+
+        [Fact]
+        public void Output_cut_by_the_tracker_is_verified_against_the_longer_saved_text()
+        {
+            var full = string.Concat(Enumerable.Repeat("line of output\n", 1000)).TrimEnd();
+            var emitted = ImeLogTracker.TruncateOutput(full);
+            Assert.EndsWith(ImeLogTracker.OutputTruncationMarker, emitted);
+            Assert.Equal(PlatformOutputVerdict.Verified, PlatformOutputJudge.Judge(Run(emitted), Saved(full)).Verdict);
+        }
+
+        [Fact]
+        public void Both_empty_is_verified_but_stderr_on_a_success_is_another_executors()
+        {
+            Assert.Equal(PlatformOutputVerdict.Verified, PlatformOutputJudge.Judge(Run(string.Empty), Saved(string.Empty)).Verdict);
+            var judgement = PlatformOutputJudge.Judge(Run(string.Empty, "Get-Item : not found"), Saved(string.Empty));
+            Assert.Equal(PlatformOutputVerdict.Foreign, judgement.Verdict);
+            Assert.Equal("stderr_on_success", judgement.Reason);
+        }
+
+        [Fact]
+        public void Explicitly_empty_emitted_output_against_saved_text_is_foreign()
+        {
+            Assert.Equal(PlatformOutputVerdict.Foreign, PlatformOutputJudge.Judge(Run(string.Empty), Saved(OwnStdout)).Verdict);
+            Assert.Equal(PlatformOutputVerdict.Foreign, PlatformOutputJudge.Judge(Run(OwnStdout), Saved(string.Empty)).Verdict);
+        }
+
+        [Fact]
+        public void Output_never_read_is_completed_from_the_saved_text_and_the_exit_code_stands()
+        {
+            var judgement = PlatformOutputJudge.Judge(Run(null), Saved(OwnStdout));
+            Assert.Equal(PlatformOutputVerdict.Repaired, judgement.Verdict);
+            Assert.Equal("stdout_missing", judgement.Reason);
+            Assert.Equal(OwnStdout, judgement.Stdout);
+            Assert.Equal(PlatformOutputVerdict.NotComparable, PlatformOutputJudge.Judge(Run(null), Saved(string.Empty)).Verdict);
+        }
+
+        [Fact]
+        public void Stdout_containing_the_output_error_separator_is_repaired_not_foreign()
+        {
+            // "write output done. output = X, error = " with X = "Copying files, error = 0 errors\nDone": the
+            // lazy split leaves "Copying files" as stdout and the rest as stderr.
+            var judgement = PlatformOutputJudge.Judge(
+                Run("Copying files", "0 errors\nDone, error ="),
+                Saved("Copying files, error = 0 errors\r\nDone"));
+            Assert.Equal(PlatformOutputVerdict.Repaired, judgement.Verdict);
+            Assert.Equal("stdout_split", judgement.Reason);
+            Assert.Equal("Copying files, error = 0 errors\nDone", judgement.Stdout);
+            Assert.Equal(string.Empty, judgement.Stderr);
+        }
+
+        [Fact]
+        public void A_prefix_without_the_split_explanation_is_foreign()
+        {
+            Assert.Equal(PlatformOutputVerdict.Foreign, PlatformOutputJudge.Judge(Run("Detected"), Saved("Detected and repaired")).Verdict);
+        }
+
+        [Fact]
+        public void Failed_with_stderr_is_judged_on_stderr()
+        {
+            Assert.Equal(PlatformOutputVerdict.Verified,
+                PlatformOutputJudge.Judge(Run("partial", "Access denied", 1, "Failed"), Saved("Access denied\r\n", "Failed", 99)).Verdict);
+
+            var missing = PlatformOutputJudge.Judge(Run(null, null, 1, "Failed"), Saved("Access denied", "Failed", 99));
+            Assert.Equal(PlatformOutputVerdict.Repaired, missing.Verdict);
+            Assert.Null(missing.Stdout);
+            Assert.Equal("Access denied", missing.Stderr);
+
+            var foreign = PlatformOutputJudge.Judge(Run("Detected", string.Empty, 0, "Failed"), Saved("Access denied", "Failed", 99));
+            Assert.Equal(PlatformOutputVerdict.Foreign, foreign.Verdict);
+            Assert.Equal(string.Empty, foreign.Stdout);
+            Assert.Equal("Access denied", foreign.Stderr);
+        }
+
+        [Fact]
+        public void Results_without_saved_output_or_from_another_run_are_not_compared()
+        {
+            Assert.Equal("no_saved_output", PlatformOutputJudge.Judge(Run(OwnStdout, null, 1, "Failed"), Saved("1", "Failed", 1)).Reason);
+            var hashMismatch = new SavedScriptResult { UserId = DeviceUser, PolicyId = PolicyA, Result = "Failed", ErrorCode = 2, ResultDetails = "Hash mismatch" };
+            Assert.Equal("no_execution_message", PlatformOutputJudge.Judge(Run(OwnStdout, null, 1, "Failed"), hashMismatch).Reason);
+            Assert.Equal("result_differs", PlatformOutputJudge.Judge(Run(OwnStdout), Saved("Access denied", "Failed", 99)).Reason);
+            // A result derived from the exit code (fallback) is not IME's — the saved one is.
+            Assert.Equal(PlatformOutputVerdict.Verified,
+                PlatformOutputJudge.Judge(Run(OwnStdout, null, 1, "Failed", "agentexecutor_fallback"), Saved(OwnStdout)).Verdict);
+        }
+
+        // ── PlatformScriptRunRegister ───────────────────────────────────────────
+
+        private static ScriptExecutionState Emitted(string policyId, string? stdout, int? exitCode = 0, string? userId = DeviceUser, string runId = "run-1")
+            => new ScriptExecutionState { PolicyId = policyId, ScriptType = "platform", UserId = userId, RunId = runId, Result = "Success", ResultSource = "ime_policy_result", ExitCode = exitCode, Stdout = stdout };
+
+        [Fact]
+        public void A_save_is_paired_only_after_the_tracker_read_past_it_and_the_run_was_emitted()
+        {
+            var runs = new PlatformScriptRunRegister();
+            runs.NoteStarted(DeviceUser, PolicyA, T0);
+            var seen = T0.AddSeconds(30);
+
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(DeviceUser, PolicyA, seen, out _));
+            runs.NotePassCompleted(seen.AddSeconds(1));
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(DeviceUser, PolicyA, seen, out _)); // pass started too early
+            runs.NotePassCompleted(seen + PlatformScriptRunRegister.TrackerCatchUp);
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(DeviceUser, PolicyA, seen, out _)); // run not emitted yet
+
+            runs.NoteEmitted(Emitted(PolicyA, OwnStdout), T0.AddSeconds(40));
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, seen, out var run));
+            Assert.Equal("run-1", run!.RunId);
+            Assert.Equal(OwnStdout, run.Stdout);
+            Assert.Equal(PlatformRunClaim.None, runs.TryClaim(DeviceUser, PolicyA, seen, out _)); // never twice
+        }
+
+        [Fact]
+        public void A_new_start_replaces_the_latest_run_of_its_key_and_other_users_stay_apart()
+        {
+            var runs = new PlatformScriptRunRegister();
+            runs.NoteStarted(DeviceUser, PolicyA, T0);
+            runs.NoteEmitted(Emitted(PolicyA, "first run"), T0.AddSeconds(5));
+            runs.NoteStarted(DeviceUser, PolicyA, T0.AddMinutes(30));
+            runs.NoteEmitted(Emitted(PolicyA, "second run", runId: "run-2"), T0.AddMinutes(30).AddSeconds(5));
+            const string user = "6c3f8a20-1d5e-4b97-8f4a-0e2d6b9c7a13";
+            runs.NoteStarted(user, PolicyA, T0.AddMinutes(31));
+            runs.NotePassCompleted(T0.AddHours(1));
+
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, T0.AddMinutes(31), out var run));
+            Assert.Equal("second run", run!.Stdout);
+            Assert.Equal(PlatformRunClaim.Wait, runs.TryClaim(user, PolicyA, T0.AddMinutes(32), out _));
+            Assert.Equal(PlatformRunClaim.None, runs.TryClaim(DeviceUser, PolicyB, T0.AddMinutes(32), out _));
+        }
+
+        [Fact]
+        public void A_run_without_a_readable_user_id_is_claimed_by_its_policy()
+        {
+            var runs = new PlatformScriptRunRegister();
+            runs.NoteStarted(null, PolicyA, T0);
+            runs.NoteEmitted(Emitted(PolicyA, OwnStdout, userId: null), T0.AddSeconds(5));
+            runs.NotePassCompleted(T0.AddMinutes(5));
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, T0.AddMinutes(1), out _));
+        }
+
+        [Fact]
+        public void Register_keeps_the_newest_runs_and_its_counters_report_each_change_once()
+        {
+            var runs = new PlatformScriptRunRegister();
+            for (var i = 0; i <= PlatformScriptRunRegister.MaxRuns; i++)
+                runs.NoteStarted(DeviceUser, Guid.NewGuid().ToString("D"), T0.AddSeconds(i));
+            runs.NoteStarted(DeviceUser, PolicyA, T0.AddHours(1));
+            runs.NoteEmitted(Emitted(PolicyA, OwnStdout), T0.AddHours(1));
+            runs.NotePassCompleted(T0.AddHours(2));
+            Assert.Equal(PlatformRunClaim.Claimed, runs.TryClaim(DeviceUser, PolicyA, T0.AddHours(1), out _));
+
+            Assert.False(runs.ConsumeCountersChanged());
+            runs.CountVerified();
+            runs.CountCorrected();
+            Assert.True(runs.ConsumeCountersChanged());
+            Assert.False(runs.ConsumeCountersChanged());
+            Assert.Equal(1, runs.Verified);
+            runs.RestoreCounters(7, 3);
+            Assert.Equal(7, runs.Verified);
+            Assert.Equal(3, runs.Corrected);
+        }
+
+        // ── observer flow ───────────────────────────────────────────────────────
+
+        private sealed class Fixture
+        {
+            public readonly FakeSignalIngressSink Sink = new FakeSignalIngressSink();
+            public readonly VirtualClock Clock = new VirtualClock(T0);
+            public readonly PlatformScriptRunRegister Runs = new PlatformScriptRunRegister();
+            public Dictionary<string, SavedScriptResult> Registry = new Dictionary<string, SavedScriptResult>(StringComparer.OrdinalIgnoreCase);
+            public readonly ImeRegistryScriptResultObserver Observer;
+
+            public Fixture()
+            {
+                Observer = new ImeRegistryScriptResultObserver(Runs, new InformationalEventPost(Sink, Clock), null, Clock,
+                    () => new Dictionary<string, SavedScriptResult>(Registry, StringComparer.OrdinalIgnoreCase));
+            }
+
+            public void Save(SavedScriptResult saved) => Registry[ImeRegistryScriptResultObserver.KeyOf(saved.UserId, saved.PolicyId)] = saved;
+
+            /// <summary>The tracker emitted a run, then kept polling past the save.</summary>
+            public void EmitRun(string policyId, string? stdout, int? exitCode, string runId)
+            {
+                Runs.NoteStarted(DeviceUser, policyId, Clock.UtcNow);
+                Runs.NoteEmitted(Emitted(policyId, stdout, exitCode, runId: runId), Clock.UtcNow);
+            }
+
+            public void TrackerCaughtUp() => Runs.NotePassCompleted(Clock.UtcNow);
+
+            public IReadOnlyList<FakeSignalIngressSink.PostedSignal> Corrections()
+                => Sink.Posted.Where(p => p.Payload != null
+                    && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                    && et == SharedEventTypes.ScriptOutputReconciliation).ToList();
+        }
+
+        [Fact]
+        public void Field_case_end_to_end_the_save_corrects_the_run_with_a_warning_naming_it()
+        {
+            var f = new Fixture();
+            f.Save(Saved("an older run of another policy", policy: PolicyB, stamp: "10/2/2026 8:00:00 AM"));
+            f.Observer.Tick("baseline");
+
+            f.EmitRun(PolicyA, ForeignStdout, 1, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.Clock.Advance(TimeSpan.FromSeconds(1));
+            f.Observer.Tick("registry_change");
+            Assert.Empty(f.Corrections()); // the tracker has not read past the save yet
+
+            f.Clock.Advance(PlatformScriptRunRegister.TrackerCatchUp);
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            var correction = Assert.Single(f.Corrections());
+            var data = correction.Payload!;
+            Assert.Equal(PolicyA, data["policyId"]);
+            Assert.Equal("platform", data["scriptType"]);
+            Assert.Equal("run-a", data["runId"]);
+            Assert.Equal("foreign", data["outcome"]);
+            Assert.Equal("stdout_differs", data["reason"]);
+            Assert.Equal("Success", data["result"]);
+            Assert.Equal(OwnStdout, data["stdout"]);
+            Assert.Equal(string.Empty, data["stderr"]);
+            Assert.Equal("1", data["previousExitCode"]);
+            Assert.Equal("0", data["registryErrorCode"]);
+            Assert.Equal("Warning", data[SignalPayloadKeys.Severity]);
+            Assert.Equal("true", data[SignalPayloadKeys.ImmediateUpload]);
+            Assert.DoesNotContain("exitCode", data.Keys);
+            Assert.Equal(1, f.Runs.Corrected);
+            Assert.Equal(0, f.Runs.Verified);
+
+            // The same save read again changes nothing.
+            f.Clock.Advance(TimeSpan.FromMinutes(1));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+            Assert.Single(f.Corrections());
+        }
+
+        [Fact]
+        public void Confirmed_output_is_counted_and_emits_nothing()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.EmitRun(PolicyA, OwnStdout, 0, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.Clock.Advance(TimeSpan.FromSeconds(1));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            Assert.Empty(f.Corrections());
+            Assert.Equal(1, f.Runs.Verified);
+        }
+
+        [Fact]
+        public void Completed_output_is_an_info_event_that_keeps_the_exit_code()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.EmitRun(PolicyA, null, 0, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.Clock.Advance(TimeSpan.FromSeconds(1));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            var data = Assert.Single(f.Corrections()).Payload!;
+            Assert.Equal("repaired", data["outcome"]);
+            Assert.Equal("Info", data[SignalPayloadKeys.Severity]);
+            Assert.DoesNotContain("previousExitCode", data.Keys);
+        }
+
+        [Fact]
+        public void A_save_seen_before_its_run_was_emitted_waits_for_the_emit()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.Runs.NoteStarted(DeviceUser, PolicyA, f.Clock.UtcNow); // result held for its end block
+            f.Save(Saved(OwnStdout));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+            Assert.Equal(0, f.Runs.Verified + f.Runs.Corrected);
+
+            f.Runs.NoteEmitted(Emitted(PolicyA, ForeignStdout, 1, runId: "run-a"), f.Clock.UtcNow);
+            f.Clock.Advance(TimeSpan.FromSeconds(60));
+            f.Observer.Tick("periodic");
+            Assert.Equal("foreign", Assert.Single(f.Corrections()).Payload!["outcome"]);
+        }
+
+        [Fact]
+        public void A_save_no_run_claims_within_the_expiry_is_dropped()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            f.Save(Saved(OwnStdout));
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(ImeRegistryScriptResultObserver.PendingExpiry);
+            f.TrackerCaughtUp();
+            f.Runs.NoteStarted(DeviceUser, PolicyA, f.Clock.UtcNow);
+            f.Observer.Tick("periodic"); // waits for the emit — and expires
+
+            f.Runs.NoteEmitted(Emitted(PolicyA, ForeignStdout, 1, runId: "run-a"), f.Clock.UtcNow);
+            f.Clock.Advance(TimeSpan.FromSeconds(60));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+            Assert.Empty(f.Corrections());
+        }
+
+        [Fact]
+        public void Saves_from_before_the_agent_started_are_the_silent_baseline()
+        {
+            var f = new Fixture();
+            f.EmitRun(PolicyA, ForeignStdout, 1, "run-a");
+            f.Save(Saved(OwnStdout));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("baseline");
+            f.Clock.Advance(TimeSpan.FromMinutes(1));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            Assert.Empty(f.Corrections());
+            Assert.Equal(0, f.Runs.Verified + f.Runs.Corrected);
+        }
+
+        [Fact]
+        public void Corrections_beyond_the_cap_are_counted_but_not_emitted()
+        {
+            var f = new Fixture();
+            f.Observer.Tick("baseline");
+            var policies = Enumerable.Range(0, ImeRegistryScriptResultObserver.MaxCorrectionsPerSession + 3).Select(_ => Guid.NewGuid().ToString("D")).ToList();
+            foreach (var policy in policies)
+            {
+                f.EmitRun(policy, ForeignStdout, 1, "run-" + policy);
+                f.Save(Saved(OwnStdout, policy: policy));
+            }
+            f.Observer.Tick("registry_change");
+            f.Clock.Advance(TimeSpan.FromSeconds(3));
+            f.TrackerCaughtUp();
+            f.Observer.Tick("periodic");
+
+            Assert.Equal(ImeRegistryScriptResultObserver.MaxCorrectionsPerSession, f.Corrections().Count);
+            Assert.Equal(policies.Count, f.Runs.Corrected);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/OobeUpdateRegistrySnapshotTests.cs

@@ -0,0 +1,128 @@
+#nullable enable
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// The OOBE update registry snapshot (D-310, S4/S5): one readable, bounded line per key, for
+    /// agent.log and the <c>oobe_update_state</c> event. The registry read itself is a thin wrapper.
+    /// </summary>
+    public sealed class OobeUpdateRegistrySnapshotTests
+    {
+        private static KeyValuePair<string, object> Entry(string name, object value) => new KeyValuePair<string, object>(name, value);
+
+        [Fact]
+        public void Values_AreFormattedByType()
+        {
+            Assert.Equal("1", OobeUpdateRegistrySnapshot.FormatValue(1));
+            Assert.Equal("5000000000", OobeUpdateRegistrySnapshot.FormatValue(5000000000L));
+            Assert.Equal("Succeeded", OobeUpdateRegistrySnapshot.FormatValue("Succeeded"));
+            Assert.Equal("a|b", OobeUpdateRegistrySnapshot.FormatValue(new[] { "a", "b" }));
+            Assert.Equal("(binary 3 bytes)", OobeUpdateRegistrySnapshot.FormatValue(new byte[] { 1, 2, 3 }));
+            Assert.Equal("(null)", OobeUpdateRegistrySnapshot.FormatValue(null!));
+        }
+
+        [Fact]
+        public void LongValues_AreTruncated()
+        {
+            var formatted = OobeUpdateRegistrySnapshot.FormatValue(new string('x', 500));
+            Assert.Equal(OobeUpdateRegistrySnapshot.MaxValueLength + 1, formatted.Length);
+            Assert.EndsWith("…", formatted);
+        }
+
+        [Fact]
+        public void Entries_AreOrderedByName()
+        {
+            var line = OobeUpdateRegistrySnapshot.FormatEntries(new[]
+            {
+                Entry("ExpeditedUpdateStatus", 2),
+                Entry("EnableExpeditedUpdate", 1),
+                Entry("", "default"),
+            }, oobeOnly: false);
+
+            Assert.Equal("(default)=default, EnableExpeditedUpdate=1, ExpeditedUpdateStatus=2", line);
+        }
+
+        [Fact]
+        public void PolicyManagerSystemKey_KeepsOnlyOobeValues()
+        {
+            // That key holds every System policy of the device; only the OOBE ones matter here.
+            var line = OobeUpdateRegistrySnapshot.FormatEntries(new[]
+            {
+                Entry("AllowTelemetry", 1),
+                Entry("AllowOOBEUpdates", 1),
+                Entry("AllowOOBEUpdates_ProviderSet", 1),
+            }, oobeOnly: true);
+
+            Assert.Equal("AllowOOBEUpdates=1, AllowOOBEUpdates_ProviderSet=1", line);
+            Assert.Equal("(no OOBE values)", OobeUpdateRegistrySnapshot.FormatEntries(new[] { Entry("AllowTelemetry", 1) }, oobeOnly: true));
+            Assert.Equal("(no values)", OobeUpdateRegistrySnapshot.FormatEntries(new KeyValuePair<string, object>[0], oobeOnly: false));
+        }
+
+        [Fact]
+        public void ManyEntries_AreCapped_AndSaySo()
+        {
+            var entries = Enumerable.Range(0, OobeUpdateRegistrySnapshot.MaxEntries + 5)
+                .Select(i => Entry($"Value{i:000}", i));
+
+            var line = OobeUpdateRegistrySnapshot.FormatEntries(entries, oobeOnly: false);
+
+            Assert.EndsWith("… (+5 more)", line);
+        }
+
+        [Fact]
+        public void Describe_CountsOnlyOobeValues_OfThePolicyManagerSystemKey()
+        {
+            var policy = OobeUpdateRegistrySnapshot.Describe("policyManagerSystem", OobeUpdateRegistrySnapshot.PolicyManagerSystemKey,
+                new[] { Entry("AllowTelemetry", 1) }, new string[0]);
+            Assert.True(policy.Exists);
+            Assert.False(policy.HasValues);
+
+            var oobe = OobeUpdateRegistrySnapshot.Describe("policyManagerSystem", OobeUpdateRegistrySnapshot.PolicyManagerSystemKey,
+                new[] { Entry("AllowTelemetry", 1), Entry("AllowOOBEUpdates", 1) }, new string[0]);
+            Assert.True(oobe.HasValues);
+            Assert.Equal("AllowOOBEUpdates=1", oobe.Line);
+        }
+
+        [Fact]
+        public void Describe_SubkeysAlone_AreNoValues()
+        {
+            var state = OobeUpdateRegistrySnapshot.Describe("ndup", @"SOFTWARE\Microsoft\Windows\CurrentVersion\NDUP",
+                new KeyValuePair<string, object>[0], new[] { "Updates" });
+
+            Assert.False(state.HasValues);
+            Assert.Equal("(no values) | subkeys: Updates", state.Line);
+        }
+
+        [Fact]
+        public void Keys_HaveDistinctAliases()
+        {
+            // The aliases are the data keys of oobe_update_state.
+            Assert.Equal(OobeUpdateRegistrySnapshot.Keys.Length,
+                OobeUpdateRegistrySnapshot.Keys.Select(k => k.Alias).Distinct().Count());
+        }
+
+        [Fact]
+        public void Read_ReturnsEveryKey_FromTheRealRegistry()
+        {
+            var states = OobeUpdateRegistrySnapshot.Read();
+
+            Assert.Equal(OobeUpdateRegistrySnapshot.Keys.Select(k => k.Path), states.Select(s => s.Path));
+            Assert.All(states.Where(s => !s.Exists), s => Assert.False(s.HasValues));
+        }
+
+        [Fact]
+        public void Log_ToleratesMissingLoggerOrStates()
+        {
+            using var tmp = new TempDirectory();
+            OobeUpdateRegistrySnapshot.Log(new AgentLogger(tmp.Path, AgentLogLevel.Info), "test", OobeUpdateRegistrySnapshot.Read());
+            OobeUpdateRegistrySnapshot.Log(null!, "test", OobeUpdateRegistrySnapshot.Read());
+            OobeUpdateRegistrySnapshot.Log(new AgentLogger(tmp.Path, AgentLogLevel.Info), "test", null!);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/OobeUpdateTelemetryTests.cs

@@ -0,0 +1,260 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.Shared;
+using AutopilotMonitor.Shared.Models;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// Measurement telemetry of the OOBE update page (D-310): <c>oobe_update_page</c> per
+    /// update-page record and <c>oobe_update_state</c> for the registry behind it — Debug, bounded
+    /// per run, the state only when a key holds values and the content changed.
+    /// </summary>
+    public sealed class OobeUpdateTelemetryTests : IDisposable
+    {
+        private static readonly DateTime At = new DateTime(2026, 10, 2, 9, 0, 0, DateTimeKind.Utc);
+
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly FakeSignalIngressSink _sink = new FakeSignalIngressSink();
+        private IReadOnlyList<OobeUpdateRegistrySnapshot.KeyState> _registry = Array.Empty<OobeUpdateRegistrySnapshot.KeyState>();
+
+        public void Dispose() => _tmp.Dispose();
+
+        private OobeUpdateTelemetry Build(Func<IReadOnlyList<OobeUpdateRegistrySnapshot.KeyState>>? reader = null) =>
+            new OobeUpdateTelemetry("sess-oobe", "tenant-oobe",
+                new InformationalEventPost(_sink, new VirtualClock(At)),
+                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                reader ?? (() => _registry));
+
+        private IReadOnlyList<FakeSignalIngressSink.PostedSignal> ByType(string eventType) =>
+            _sink.Posted.Where(p =>
+                p.Kind == DecisionSignalKind.InformationalEvent
+                && p.Payload != null
+                && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                && et == eventType).ToList();
+
+        private static IReadOnlyDictionary<string, object> Data(FakeSignalIngressSink.PostedSignal posted) =>
+            (IReadOnlyDictionary<string, object>)posted.TypedPayload!;
+
+        private static OobeUpdateRegistrySnapshot.KeyState Key(string alias, string? line) =>
+            line == null
+                ? new OobeUpdateRegistrySnapshot.KeyState(alias, $@"SOFTWARE\{alias}", exists: false, hasValues: false, line: null)
+                : new OobeUpdateRegistrySnapshot.KeyState(alias, $@"SOFTWARE\{alias}", exists: true, hasValues: true, line: line);
+
+        // ------------------------------------------------------------- oobe_update_page ----
+
+        [Fact]
+        public void Page_IsReported_WithItsEventTime_AndFields()
+        {
+            Build().ReportPage(
+                new OobeUpdatePageRecord(OobeUpdateVocabulary.PageStopped, 62405, page: "OobeNDUP", result: "success"),
+                At.AddMinutes(-3), isBackfill: true);
+
+            var page = Assert.Single(ByType(Constants.EventTypes.OobeUpdatePage));
+            Assert.Equal(At.AddMinutes(-3), page.OccurredAtUtc);
+            Assert.Equal("Debug", page.Payload![SignalPayloadKeys.Severity]);
+            var data = Data(page);
+            Assert.Equal("page_stopped", data["cxhEvent"]);
+            Assert.Equal("OobeNDUP", data["page"]);
+            Assert.Equal("success", data["result"]);
+            Assert.Equal(true, data["backfill"]);
+            Assert.Equal(1, data["occurrence"]);
+            Assert.False(data.ContainsKey("value"));
+        }
+
+        [Fact]
+        public void EventName_CarriesItsSafeValue()
+        {
+            Build().ReportPage(
+                new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62407, name: "ExpeditedUpdate_isNDUPAllowedByCSPSucceeded", value: "true"),
+                At, isBackfill: false);
+
+            var data = Data(Assert.Single(ByType(Constants.EventTypes.OobeUpdatePage)));
+            Assert.Equal("ExpeditedUpdate_isNDUPAllowedByCSPSucceeded", data["name"]);
+            Assert.Equal("true", data["value"]);
+        }
+
+        [Fact]
+        public void SamePageOrName_IsReportedAtMostThreeTimes()
+        {
+            var telemetry = Build();
+            for (var i = 0; i < 10; i++)
+            {
+                telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: "ExpeditedUpdate_progress"), At.AddSeconds(i), isBackfill: false);
+            }
+            telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.PageStopped, 62405, page: "OobeNDUP", result: "success"), At.AddMinutes(1), isBackfill: false);
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage);
+            Assert.Equal(OobeUpdateTelemetry.MaxPageEventsPerKey + 1, pages.Count);
+            Assert.Equal(new object[] { 1, 2, 3 }, pages.Take(3).Select(p => Data(p)["occurrence"]).ToArray());
+            // The repeats do not crowd out the page end.
+            Assert.Equal("page_stopped", Data(pages.Last())["cxhEvent"]);
+        }
+
+        [Fact]
+        public void PageEvents_AreCappedPerRun_AndTheCapIsMarkedOnce()
+        {
+            var telemetry = Build();
+            for (var i = 0; i < OobeUpdateTelemetry.MaxPageEventsPerRun + 20; i++)
+            {
+                telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: $"ExpeditedUpdate_step{i}"), At.AddSeconds(i), isBackfill: false);
+            }
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage);
+            Assert.Equal(OobeUpdateTelemetry.MaxPageEventsPerRun + 1, pages.Count);
+            // A name missing after the marker proves nothing — the rules check for it.
+            var marker = Data(pages.Last());
+            Assert.Equal(OobeUpdateVocabulary.NamesCapped, marker["cxhEvent"]);
+            Assert.Equal(false, marker["backfill"]);
+            Assert.Equal(OobeUpdateTelemetry.MaxPageEventsPerRun, marker["limit"]);
+            Assert.Equal(At.AddSeconds(OobeUpdateTelemetry.MaxPageEventsPerRun), pages.Last().OccurredAtUtc); // the first name over the budget
+        }
+
+        [Fact]
+        public void BackfilledNames_HaveTheirOwnBudget()
+        {
+            // The records from before the agent started cannot spend the live page's budget.
+            var telemetry = Build();
+            for (var i = 0; i < OobeUpdateTelemetry.MaxBackfillPageEventsPerRun + 5; i++)
+            {
+                telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: $"ExpeditedUpdate_old{i}"), At.AddMinutes(-30), isBackfill: true);
+            }
+
+            Assert.True(telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: "ExpeditedUpdate_live"), At, isBackfill: false));
+
+            var markers = ByType(Constants.EventTypes.OobeUpdatePage)
+                .Where(p => (string)Data(p)["cxhEvent"] == OobeUpdateVocabulary.NamesCapped).ToList();
+            var marker = Assert.Single(markers);
+            Assert.Equal(true, Data(marker)["backfill"]);
+            Assert.Equal(OobeUpdateTelemetry.MaxBackfillPageEventsPerRun, Data(marker)["limit"]);
+        }
+
+        [Fact]
+        public void PageStartAndStop_AreReported_AfterTheNameBudgetIsSpent()
+        {
+            // The time attribution reads the update's span from the page start and stop.
+            var telemetry = Build();
+            for (var i = 0; i < OobeUpdateTelemetry.MaxPageEventsPerRun; i++)
+            {
+                Assert.True(telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: $"ExpeditedUpdate_step{i}"), At, isBackfill: false));
+            }
+
+            Assert.False(telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: "ExpeditedUpdate_late"), At, isBackfill: false));
+            Assert.False(telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.EventName, 62406, name: "ExpeditedUpdate_later"), At, isBackfill: false));
+            Assert.True(telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.PageStarted, 62404, page: "RebootNDUP"), At.AddMinutes(1), isBackfill: false));
+            Assert.True(telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.PageStopped, 62405, page: "RebootNDUP", result: "success"), At.AddMinutes(2), isBackfill: false));
+
+            var pages = ByType(Constants.EventTypes.OobeUpdatePage);
+            Assert.Equal(OobeUpdateTelemetry.MaxPageEventsPerRun + 3, pages.Count);
+            Assert.Equal(new object[] { OobeUpdateVocabulary.NamesCapped, "page_started", "page_stopped" },
+                pages.Skip(OobeUpdateTelemetry.MaxPageEventsPerRun).Select(p => Data(p)["cxhEvent"]).ToArray());
+        }
+
+        [Fact]
+        public void SamePageStart_IsReportedAtMostThreeTimes()
+        {
+            // Outside the run budget, but a page that restarts in a loop still cannot flood.
+            var telemetry = Build();
+            var reported = Enumerable.Range(0, 10)
+                .Count(i => telemetry.ReportPage(new OobeUpdatePageRecord(OobeUpdateVocabulary.PageStarted, 62404, page: "OobeNDUP"), At.AddMinutes(i), isBackfill: false));
+
+            Assert.Equal(OobeUpdateTelemetry.MaxPageEventsPerKey, reported);
+        }
+
+        // ------------------------------------------------------------ oobe_update_state ----
+
+        [Fact]
+        public void State_WithoutValues_IsNotReported()
+        {
+            _registry = new[] { Key("setupOobeNdup", null), Key("policiesOobe", null) };
+
+            Build().ReportState(OobeUpdateTelemetry.Moments.AgentStart);
+
+            Assert.Empty(ByType(Constants.EventTypes.OobeUpdateState));
+        }
+
+        [Fact]
+        public void State_ReportsOnlyKeysWithValues_UnderTheirAlias()
+        {
+            _registry = new[]
+            {
+                Key("setupOobeNdup", "EnableExpeditedUpdate=1, EnableExpeditedUpdateSyncDownloadCompleted=1"),
+                Key("ndup", null),
+                new OobeUpdateRegistrySnapshot.KeyState("policyManagerSystem", "x", exists: true, hasValues: false, line: "(no OOBE values)"),
+                Key("espSetupPolicy", "InstallQualityUpdates=1"),
+            };
+
+            Build().ReportState(OobeUpdateTelemetry.Moments.UpdatePageStopped, "OobeNDUP");
+
+            var state = Assert.Single(ByType(Constants.EventTypes.OobeUpdateState));
+            Assert.Equal("Debug", state.Payload![SignalPayloadKeys.Severity]);
+            var data = Data(state);
+            Assert.Equal("update_page_stopped", data["moment"]);
+            Assert.Equal("OobeNDUP", data["page"]);
+            Assert.Equal(2, data["keysWithValues"]);
+            Assert.Equal("EnableExpeditedUpdate=1, EnableExpeditedUpdateSyncDownloadCompleted=1", data["setupOobeNdup"]);
+            Assert.Equal("InstallQualityUpdates=1", data["espSetupPolicy"]);
+            Assert.False(data.ContainsKey("ndup"));
+            Assert.False(data.ContainsKey("policyManagerSystem"));
+        }
+
+        [Fact]
+        public void UnchangedState_IsReportedOnce_AChangeAgain()
+        {
+            var telemetry = Build();
+            _registry = new[] { Key("espSetupPolicy", "InstallQualityUpdates=1") };
+
+            telemetry.ReportState(OobeUpdateTelemetry.Moments.AgentStart);
+            telemetry.ReportState(OobeUpdateTelemetry.Moments.UpdatePageStarted, "OobeNDUP");
+            _registry = new[] { Key("espSetupPolicy", "InstallQualityUpdates=1"), Key("setupOobeNdup", "EnableExpeditedUpdate=1") };
+            telemetry.ReportState(OobeUpdateTelemetry.Moments.UpdatePageStopped, "OobeNDUP");
+            telemetry.ReportState(OobeUpdateTelemetry.Moments.AgentStop);
+
+            var states = ByType(Constants.EventTypes.OobeUpdateState);
+            Assert.Equal(new object[] { "agent_start", "update_page_stopped" }, states.Select(s => Data(s)["moment"]).ToArray());
+        }
+
+        [Fact]
+        public void StateEvents_AreCappedPerRun()
+        {
+            var telemetry = Build();
+            for (var i = 0; i < OobeUpdateTelemetry.MaxStateEventsPerRun + 4; i++)
+            {
+                _registry = new[] { Key("setupOobeNdup", $"ExpeditedUpdateStatus={i}") };
+                telemetry.ReportState(OobeUpdateTelemetry.Moments.UpdatePageStarted, "OobeNDUP");
+            }
+
+            Assert.Equal(OobeUpdateTelemetry.MaxStateEventsPerRun, ByType(Constants.EventTypes.OobeUpdateState).Count);
+        }
+
+        [Fact]
+        public void LongLines_AreTruncated()
+        {
+            _registry = new[] { Key("ndupUpdates", new string('x', 3000)) };
+
+            Build().ReportState(OobeUpdateTelemetry.Moments.AgentStart);
+
+            var line = (string)Data(Assert.Single(ByType(Constants.EventTypes.OobeUpdateState)))["ndupUpdates"];
+            Assert.Equal(OobeUpdateTelemetry.MaxStateLineLength + 1, line.Length);
+            Assert.EndsWith("…", line);
+        }
+
+        [Fact]
+        public void FailingRegistryRead_ReportsNothing_AndDoesNotThrow()
+        {
+            Build(() => throw new UnauthorizedAccessException("denied")).ReportState(OobeUpdateTelemetry.Moments.AgentStart);
+
+            Assert.Empty(_sink.Posted);
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/ProvisioningStatusTrackerAccountSetupActivityTests.cs

@@ -83,6 +83,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             using var f = new Fixture();
             Assert.False(f.Tracker.HasAccountSetupActivity);
             Assert.False(f.Tracker.HasAccountSetupProgress);
+            Assert.Null(f.Tracker.AccountSetupProgressIfRead);
         }
 
         [Fact]
@@ -97,6 +98,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
 
             Assert.True(f.Tracker.HasAccountSetupActivity);
             Assert.False(f.Tracker.HasAccountSetupProgress);
+            // Read and untouched — the only state the WhiteGlove sealing gate treats as "false".
+            Assert.False(f.Tracker.AccountSetupProgressIfRead);
         }
 
         [Fact]
@@ -108,6 +111,7 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
 
             Assert.True(f.Tracker.HasAccountSetupActivity);
             Assert.True(f.Tracker.HasAccountSetupProgress);
+            Assert.True(f.Tracker.AccountSetupProgressIfRead);
         }
 
         [Theory]
@@ -138,5 +142,18 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
 
             Assert.False(f.Tracker.HasAccountSetupProgress);
         }
+
+        [Fact]
+        public void OnlyDeviceSetupRead_AccountSetupProgressIsUnknown()
+        {
+            // Adversarial for the WhiteGlove sealing gate: the tracker holds DeviceSetup data but
+            // has not read the AccountSetup category — that must be "unknown", never "untouched".
+            using var f = new Fixture();
+            f.Tracker.ProcessCategoryStatusForTest("DeviceSetupCategory.Status",
+                "{\"categoryState\":\"inProgress\",\"DeviceSetup.AppsSubcategory\":{\"subcategoryState\":\"inProgress\"}}");
+
+            Assert.Null(f.Tracker.AccountSetupProgressIfRead);
+            Assert.False(f.Tracker.HasAccountSetupProgress);
+        }
     }
 }

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/ProvisioningStatusTrackerPendingFailureTests.cs

@@ -0,0 +1,92 @@
+using System;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// <see cref="ProvisioningStatusTracker.TryGetPendingFailureArgs"/> exposes the registry
+    /// failure detail while its settle window is open and nothing once the window has fired —
+    /// the coordinator reads it when a Shell-Core failure terminalises first (session 683f1eff).
+    /// </summary>
+    public sealed class ProvisioningStatusTrackerPendingFailureTests
+    {
+        private static readonly DateTime Fixed = new DateTime(2026, 9, 8, 18, 11, 2, DateTimeKind.Utc);
+
+        private const string InProgressJson = @"{
+            ""categorySucceeded"": null,
+            ""AppsSubcategory"": {""subcategoryState"":""inProgress"",""subcategoryStatusText"":""Apps (Working)""}
+        }";
+        private const string AppsFailedJson = @"{
+            ""categorySucceeded"": null,
+            ""AppsSubcategory"": {""subcategoryState"":""failed"",""subcategoryStatusText"":""Apps (0x80070652)""}
+        }";
+
+        private sealed class Fixture : IDisposable
+        {
+            public TempDirectory Tmp { get; } = new TempDirectory();
+            public ProvisioningStatusTracker Tracker { get; }
+
+            public Fixture()
+            {
+                var post = new InformationalEventPost(new FakeSignalIngressSink(), new VirtualClock(Fixed));
+                var logger = new AgentLogger(Tmp.Path, AgentLogLevel.Info);
+                Tracker = new ProvisioningStatusTracker(
+                    sessionId: "S1",
+                    tenantId: "T1",
+                    post: post,
+                    logger: logger,
+                    appxScanner: new FakeAppxDeploymentFailureScanner(),
+                    backgroundDispatcher: action => action());
+            }
+
+            public void Dispose()
+            {
+                Tracker.Dispose();
+                Tmp.Dispose();
+            }
+        }
+
+        [Fact]
+        public void Nothing_pending_before_any_failure()
+        {
+            using var f = new Fixture();
+            Assert.Null(f.Tracker.TryGetPendingFailureArgs());
+
+            f.Tracker.ProcessCategoryStatusForTest("DeviceSetupCategory.Status", InProgressJson);
+            Assert.Null(f.Tracker.TryGetPendingFailureArgs());
+        }
+
+        [Fact]
+        public void Armed_settle_window_exposes_the_registry_detail()
+        {
+            using var f = new Fixture();
+            f.Tracker.ProcessCategoryStatusForTest("DeviceSetupCategory.Status", InProgressJson);
+            f.Tracker.ProcessCategoryStatusForTest("DeviceSetupCategory.Status", AppsFailedJson);
+
+            var pending = f.Tracker.TryGetPendingFailureArgs();
+
+            Assert.NotNull(pending);
+            Assert.Equal("Provisioning_DeviceSetup_Apps_Failed", pending!.FailureType);
+            Assert.Equal("0x80070652", pending.ErrorCode);
+            Assert.Equal("Apps", pending.FailedSubcategory);
+            Assert.Equal("DeviceSetup", pending.Category);
+        }
+
+        [Fact]
+        public void Expired_settle_window_leaves_nothing_pending()
+        {
+            using var f = new Fixture();
+            f.Tracker.ProcessCategoryStatusForTest("DeviceSetupCategory.Status", InProgressJson);
+            f.Tracker.ProcessCategoryStatusForTest("DeviceSetupCategory.Status", AppsFailedJson);
+
+            f.Tracker.TriggerSettleTimerForTest("DeviceSetupCategory.Status");
+
+            Assert.Null(f.Tracker.TryGetPendingFailureArgs());
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/ServicingTrackerTests.cs

@@ -0,0 +1,289 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.DecisionCore.State;
+using AutopilotMonitor.Shared;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// ServicingTracker (D-310) — the CBS servicing steps of OS updates from the Setup log. The
+    /// sequence and XML shapes are those Windows 11 writes for a cumulative update installed by
+    /// <c>UpdateAgentLCU</c>: initiate Absent → Staged, Staged reached, initiate Staged → Installed,
+    /// restart required, Installed reached after the restart.
+    /// </summary>
+    public sealed class ServicingTrackerTests : IDisposable
+    {
+        private static readonly DateTime T0 = new DateTime(2026, 9, 25, 18, 52, 37, DateTimeKind.Utc);
+        private const string Kb = "KB5099999";
+
+        private readonly TempDirectory _tmp = new TempDirectory();
+        private readonly FakeSignalIngressSink _sink = new FakeSignalIngressSink();
+        private readonly UpdateActivityTally _tally = new UpdateActivityTally();
+        private readonly List<(string Step, string Update, DateTime At)> _osActivity = new List<(string, string, DateTime)>();
+        private readonly ServicingTracker _tracker;
+        private long _nextRecordId = 1200;
+
+        public ServicingTrackerTests()
+        {
+            _tracker = NewTracker(stateDirectory: null);
+        }
+
+        public void Dispose() => _tmp.Dispose();
+
+        private ServicingTracker NewTracker(string? stateDirectory) =>
+            new ServicingTracker(
+                sessionId: "sess-cbs",
+                tenantId: "tenant-cbs",
+                post: new InformationalEventPost(_sink, new VirtualClock(T0)),
+                logger: new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                backfillEnabled: false,
+                stateDirectory: stateDirectory,
+                tally: _tally,
+                onOsUpdateActivity: (step, update, at) => _osActivity.Add((step, update, at)));
+
+        private void Process(
+            int eventId,
+            DateTime at,
+            string? initialState = null,
+            string? targetState = "Installed",
+            string? errorCode = null,
+            string? client = "UpdateAgentLCU",
+            string? package = Kb,
+            long? recordId = null,
+            ServicingTracker? tracker = null,
+            bool isBackfill = false)
+        {
+            (tracker ?? _tracker).ProcessEvent(
+                eventId: eventId,
+                recordId: recordId ?? _nextRecordId++,
+                timeCreatedUtc: at,
+                package: package,
+                initialState: initialState,
+                targetState: targetState,
+                errorCode: errorCode,
+                client: client,
+                isBackfill: isBackfill);
+        }
+
+        private IReadOnlyList<FakeSignalIngressSink.PostedSignal> Servicing() =>
+            _sink.Posted.Where(p =>
+                p.Kind == DecisionSignalKind.InformationalEvent
+                && p.Payload != null
+                && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                && et == Constants.EventTypes.WindowsUpdateServicing).ToList();
+
+        private static IReadOnlyDictionary<string, object> Data(FakeSignalIngressSink.PostedSignal s) =>
+            (IReadOnlyDictionary<string, object>)s.TypedPayload!;
+
+        [Fact]
+        public void CumulativeUpdateSequence_ListsEveryStep_AndReportsTheEngineSteps()
+        {
+            Process(ServicingTracker.EventId_InitiatingChanges, T0, initialState: "Absent", targetState: "Staged");
+            Process(ServicingTracker.EventId_StateReached, T0.AddMinutes(4), targetState: "Staged", errorCode: "0x0");
+            Process(ServicingTracker.EventId_InitiatingChanges, T0.AddMinutes(29), initialState: "Staged", targetState: "Installed");
+            Process(ServicingTracker.EventId_RebootRequired, T0.AddMinutes(33), targetState: "Installed", errorCode: "0x0");
+            // Written after the restart.
+            Process(ServicingTracker.EventId_StateReached, T0.AddMinutes(41), targetState: "Installed", errorCode: "0x0");
+
+            var rows = Servicing();
+            Assert.Equal(
+                new[] { "initiating", "state_reached", "initiating", "reboot_required", "state_reached" },
+                rows.Select(s => (string)Data(s)["step"]).ToArray());
+            Assert.All(rows, s => Assert.Equal("Info", s.Payload![SignalPayloadKeys.Severity]));
+            Assert.All(rows, s => Assert.Equal("ServicingWatcher", s.Payload![SignalPayloadKeys.Source]));
+            Assert.All(rows, s => Assert.Equal(Kb, Data(s)["package"]));
+            Assert.All(rows, s => Assert.Equal("UpdateAgentLCU", Data(s)["client"]));
+            // ErrorCode 0x0 is success, not a decoded HRESULT.
+            Assert.All(rows, s => Assert.False(Data(s).ContainsKey("hresult")));
+            Assert.Equal("Absent", Data(rows[0])["initialState"]);
+            Assert.Equal("Staged", Data(rows[0])["targetState"]);
+            Assert.Equal(T0.AddMinutes(33), rows[3].OccurredAtUtc);
+            Assert.Contains("needs a restart", rows[3].Payload![SignalPayloadKeys.Message]);
+
+            Assert.Equal(
+                new[]
+                {
+                    OsUpdateSteps.StagingStarted, OsUpdateSteps.Staged, OsUpdateSteps.InstallStarted,
+                    OsUpdateSteps.RebootRequired, OsUpdateSteps.Installed,
+                },
+                _osActivity.Select(a => a.Step).ToArray());
+            Assert.All(_osActivity, a => Assert.Equal(Kb, a.Update));
+            Assert.Equal(T0.AddMinutes(29), _osActivity[2].At);
+        }
+
+        [Theory]
+        [InlineData("CbsTask")]
+        [InlineData("DISM Package Manager Provider")]
+        [InlineData("")]
+        [InlineData(null)]
+        public void NonOsClients_AreCountedNotListed(string? client)
+        {
+            // CBS maintenance writes hundreds of these in seconds; language packs and features on
+            // demand installed by apps are not the OOBE update either.
+            Process(ServicingTracker.EventId_InitiatingChanges, T0, initialState: "Staged", targetState: "Installed",
+                client: client, package: "Microsoft-Windows-Telnet-Client-FOD-en-US");
+            Process(ServicingTracker.EventId_StateReached, T0, targetState: "Installed", errorCode: "0x0",
+                client: client, package: "Microsoft-Windows-Telnet-Client-FOD-en-US");
+
+            Assert.Empty(_sink.Posted);
+            Assert.Empty(_osActivity);
+            var counts = _tally.Snapshot().ToDictionary(kv => kv.Key, kv => kv.Value);
+            Assert.Equal(1, counts["servicing_other_1"]);
+            Assert.Equal(1, counts["servicing_other_2"]);
+        }
+
+        [Fact]
+        public void WindowsUpdateAgentClient_IsAnOsClient()
+        {
+            Process(ServicingTracker.EventId_RebootRequired, T0, client: "WindowsUpdateAgent", errorCode: "0x0");
+
+            Assert.Single(Servicing());
+            Assert.Equal(OsUpdateSteps.RebootRequired, Assert.Single(_osActivity).Step);
+        }
+
+        [Fact]
+        public void ChangeFailed_EmitsWarning_WithDecodedHResult()
+        {
+            Process(ServicingTracker.EventId_ChangeFailed, T0, targetState: "Installed", errorCode: "0x800f0922");
+
+            var s = Assert.Single(Servicing());
+            Assert.Equal("Warning", s.Payload![SignalPayloadKeys.Severity]);
+            var data = Data(s);
+            Assert.Equal("failed", data["step"]);
+            Assert.Equal("0x800F0922", data["hresult"]);
+            Assert.Equal("CBS_E_INSTALLERS_FAILED", data["hresultSymbol"]);
+            Assert.Contains("FAILED", s.Payload![SignalPayloadKeys.Message]);
+            Assert.Equal(OsUpdateSteps.Failed, Assert.Single(_osActivity).Step);
+        }
+
+        [Fact]
+        public void PartiallyInstalled_IsAFailure_AndSaysSo()
+        {
+            Process(ServicingTracker.EventId_PartiallyInstalled, T0, targetState: "Installed", errorCode: "0x800f0922");
+
+            var s = Assert.Single(Servicing());
+            Assert.Equal("failed", Data(s)["step"]);
+            Assert.Contains("partially installed", s.Payload![SignalPayloadKeys.Message]);
+            Assert.Equal(OsUpdateSteps.Failed, Assert.Single(_osActivity).Step);
+        }
+
+        [Fact]
+        public void ChangeTowardsAnotherState_IsListed_ButIsNoEngineStep()
+        {
+            // Removing a superseded package is servicing, not progress of the update install.
+            Process(ServicingTracker.EventId_InitiatingChanges, T0, initialState: "Installed", targetState: "Absent");
+
+            Assert.Single(Servicing());
+            Assert.Empty(_osActivity);
+        }
+
+        [Fact]
+        public void BackfilledRecord_KeepsItsEventTime()
+        {
+            var earlier = T0.AddMinutes(-20);
+            Process(ServicingTracker.EventId_InitiatingChanges, earlier, initialState: "Absent", targetState: "Staged", isBackfill: true);
+
+            var s = Assert.Single(Servicing());
+            Assert.Equal(earlier, s.OccurredAtUtc);
+            Assert.Equal(true, Data(s)["backfilled"]);
+            Assert.Equal(earlier, Assert.Single(_osActivity).At);
+        }
+
+        [Fact]
+        public void Watermark_SkipsEmittedRecordsAfterRestart()
+        {
+            var first = NewTracker(_tmp.Path);
+            Process(ServicingTracker.EventId_RebootRequired, T0, errorCode: "0x0", recordId: 1205, tracker: first);
+
+            var second = NewTracker(_tmp.Path);
+            second.LoadWatermark();
+            Process(ServicingTracker.EventId_RebootRequired, T0, errorCode: "0x0", recordId: 1205, tracker: second, isBackfill: true);
+            Process(ServicingTracker.EventId_StateReached, T0.AddMinutes(8), errorCode: "0x0", recordId: 1207, tracker: second);
+
+            Assert.Equal(new[] { "reboot_required", "state_reached" }, Servicing().Select(s => (string)Data(s)["step"]).ToArray());
+        }
+
+        [Fact]
+        public void SameRecordDeliveredTwice_IsListedOnce()
+        {
+            Process(ServicingTracker.EventId_RebootRequired, T0, errorCode: "0x0", recordId: 1205);
+            Process(ServicingTracker.EventId_RebootRequired, T0, errorCode: "0x0", recordId: 1205);
+
+            Assert.Single(Servicing());
+            Assert.Single(_osActivity);
+        }
+
+        [Fact]
+        public void ParseUserData_ReadsBothCbsPayloadShapes()
+        {
+            const string initiate =
+                "<Event xmlns='http://schemas.microsoft.com/win/2004/08/events/event'><System><Provider Name='Microsoft-Windows-Servicing' Guid='{bd12f3b8-fc40-4a61-a307-b7a013a069c1}'/>" +
+                "<EventID>1</EventID><Version>0</Version><Level>0</Level><Task>1</Task><Opcode>0</Opcode><Keywords>0x8000000000000000</Keywords>" +
+                "<TimeCreated SystemTime='2026-09-25T19:21:42.4486782Z'/><EventRecordID>1203</EventRecordID><Channel>Setup</Channel><Computer>DESKTOP-TEST</Computer>" +
+                "<Security UserID='S-1-5-18'/></System><UserData><CbsPackageInitiateChanges xmlns='http://manifests.microsoft.com/win/2004/08/windows/setup_provider'>" +
+                "<PackageIdentifier>KB5099999</PackageIdentifier><InitialPackageState>5064</InitialPackageState><InitialPackageStateTextized>Staged</InitialPackageStateTextized>" +
+                "<IntendedPackageState>5112</IntendedPackageState><IntendedPackageStateTextized>Installed</IntendedPackageStateTextized><Client>UpdateAgentLCU</Client>" +
+                "</CbsPackageInitiateChanges></UserData></Event>";
+            const string changeState =
+                "<Event xmlns='http://schemas.microsoft.com/win/2004/08/events/event'><System><Provider Name='Microsoft-Windows-Servicing' Guid='{bd12f3b8-fc40-4a61-a307-b7a013a069c1}'/>" +
+                "<EventID>4</EventID><TimeCreated SystemTime='2026-09-25T19:26:07.1381462Z'/><EventRecordID>1205</EventRecordID><Channel>Setup</Channel></System>" +
+                "<UserData><CbsPackageChangeState xmlns='http://manifests.microsoft.com/win/2004/08/windows/setup_provider'><PackageIdentifier>KB5099999</PackageIdentifier>" +
+                "<IntendedPackageState>5112</IntendedPackageState><IntendedPackageStateTextized>Installed</IntendedPackageStateTextized><ErrorCode>0x0</ErrorCode>" +
+                "<Client>UpdateAgentLCU</Client></CbsPackageChangeState></UserData></Event>";
+
+            var a = ServicingTracker.ParseUserData(initiate);
+            Assert.Equal("KB5099999", a["PackageIdentifier"]);
+            Assert.Equal("Staged", a["InitialPackageStateTextized"]);
+            Assert.Equal("Installed", a["IntendedPackageStateTextized"]);
+            Assert.Equal("UpdateAgentLCU", a["client"]); // case-insensitive
+            Assert.False(a.ContainsKey("ErrorCode"));
+
+            var b = ServicingTracker.ParseUserData(changeState);
+            Assert.Equal("Installed", b["IntendedPackageStateTextized"]);
+            Assert.Equal("0x0", b["ErrorCode"]);
+            Assert.False(b.ContainsKey("InitialPackageStateTextized"));
+        }
+
+        [Fact]
+        public void ParseUserData_MalformedOrWithoutUserData_ReturnsEmpty_NeverThrows()
+        {
+            Assert.Empty(ServicingTracker.ParseUserData(null));
+            Assert.Empty(ServicingTracker.ParseUserData(""));
+            Assert.Empty(ServicingTracker.ParseUserData("<not-xml"));
+            Assert.Empty(ServicingTracker.ParseUserData("<Event><System><EventID>1</EventID></System></Event>"));
+        }
+
+        [Fact]
+        public void Watermark_PersistsOnlyAfterTheEngineSignalWasHandedOver()
+        {
+            // "Reboot required" is written right before the update's restart: its engine signal
+            // must be on its way before the watermark tells the next run's backfill to skip it.
+            var path = System.IO.Path.Combine(_tmp.Path, ServicingTracker.WatermarkStateFileName);
+            bool? watermarkOnDiskAtSignal = null;
+            var tracker = new ServicingTracker(
+                sessionId: "sess-cbs",
+                tenantId: "tenant-cbs",
+                post: new InformationalEventPost(_sink, new VirtualClock(T0)),
+                logger: new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                backfillEnabled: false,
+                stateDirectory: _tmp.Path,
+                tally: _tally,
+                onOsUpdateActivity: (step, update, at) => watermarkOnDiskAtSignal = System.IO.File.Exists(path));
+
+            Process(ServicingTracker.EventId_RebootRequired, T0, errorCode: "0x0", tracker: tracker);
+
+            Assert.False(watermarkOnDiskAtSignal);
+            Assert.True(System.IO.File.Exists(path));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/StallProbeHelloWaitGuardTests.cs

@@ -0,0 +1,123 @@
+#nullable enable
+using System;
+using System.Linq;
+using AutopilotMonitor.Agent.V2.Core.Logging;
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using AutopilotMonitor.Agent.V2.Core.Orchestration;
+using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
+using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
+using AutopilotMonitor.DecisionCore.Engine;
+using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.Shared;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// A tenant-extended Hello wait runs up to 60 min — the default session_stalled threshold. While
+    /// it is pending the session waits on a bounded timer that resolves it either way, so the stall
+    /// probe holds the report back instead of flagging the session Stalled; once the wait is over
+    /// and the session is still idle the report fires, and real activity drops it. The collector
+    /// runs with no scan sources, so only the session_stalled decision is exercised.
+    /// </summary>
+    public sealed class StallProbeHelloWaitGuardTests
+    {
+        private static readonly DateTime Fixed = new DateTime(2026, 9, 29, 8, 0, 0, DateTimeKind.Utc);
+        private const double IdleAtStallThreshold = 60;
+
+        [Fact]
+        public void Session_stalled_is_held_back_while_the_hello_wait_is_pending()
+        {
+            using var tmp = new TempDirectory();
+            var ingress = new FakeSignalIngressSink();
+            var collector = NewCollector(tmp, ingress, helloWaitPending: () => true);
+
+            collector.CheckAndRunProbes(IdleAtStallThreshold);
+            collector.CheckAndRunProbes(IdleAtStallThreshold + 1);
+
+            Assert.Equal(0, StalledCount(ingress));
+        }
+
+        [Fact]
+        public void Held_back_report_fires_once_the_hello_wait_is_over_and_the_session_is_still_idle()
+        {
+            using var tmp = new TempDirectory();
+            var ingress = new FakeSignalIngressSink();
+            var pending = true;
+            var collector = NewCollector(tmp, ingress, helloWaitPending: () => pending);
+
+            collector.CheckAndRunProbes(IdleAtStallThreshold);
+            Assert.Equal(0, StalledCount(ingress));
+
+            // hello_safety resolved (a deadline fire is no activity, so no ResetProbes): the next
+            // tick emits the held-back report — once.
+            pending = false;
+            collector.CheckAndRunProbes(IdleAtStallThreshold + 1);
+            collector.CheckAndRunProbes(IdleAtStallThreshold + 2);
+
+            Assert.Equal(1, StalledCount(ingress));
+        }
+
+        [Fact]
+        public void Real_activity_drops_the_held_back_report()
+        {
+            using var tmp = new TempDirectory();
+            var ingress = new FakeSignalIngressSink();
+            var pending = true;
+            var collector = NewCollector(tmp, ingress, helloWaitPending: () => pending);
+
+            collector.CheckAndRunProbes(IdleAtStallThreshold);
+            pending = false;
+            collector.ResetProbes();
+            collector.CheckAndRunProbes(1);
+            Assert.Equal(0, StalledCount(ingress));
+
+            // A new idle window reaches the threshold again — the fire-once report is still unused.
+            collector.CheckAndRunProbes(IdleAtStallThreshold);
+            Assert.Equal(1, StalledCount(ingress));
+        }
+
+        [Fact]
+        public void Without_a_hello_wait_probe_session_stalled_fires_as_before()
+        {
+            using var tmp = new TempDirectory();
+            var ingress = new FakeSignalIngressSink();
+            var collector = NewCollector(tmp, ingress, helloWaitPending: null);
+
+            collector.CheckAndRunProbes(IdleAtStallThreshold);
+
+            Assert.Equal(1, StalledCount(ingress));
+        }
+
+        [Fact]
+        public void A_throwing_hello_wait_probe_never_costs_the_stall_report()
+        {
+            using var tmp = new TempDirectory();
+            var ingress = new FakeSignalIngressSink();
+            var collector = NewCollector(tmp, ingress, helloWaitPending: () => throw new InvalidOperationException("probe down"));
+
+            collector.CheckAndRunProbes(IdleAtStallThreshold);
+
+            Assert.Equal(1, StalledCount(ingress));
+        }
+
+        private static StallProbeCollector NewCollector(TempDirectory tmp, FakeSignalIngressSink ingress, Func<bool>? helloWaitPending) =>
+            new StallProbeCollector(
+                sessionId: "S1",
+                tenantId: "T1",
+                post: new InformationalEventPost(ingress, new VirtualClock(Fixed)),
+                logger: new AgentLogger(tmp.Path, AgentLogLevel.Info),
+                thresholdsMinutes: new[] { 60 },
+                traceIndices: Array.Empty<int>(),
+                sources: Array.Empty<string>(),
+                sessionStalledAfterProbeIndex: 1,
+                helloWaitPending: helloWaitPending);
+
+        private static int StalledCount(FakeSignalIngressSink ingress) =>
+            ingress.Posted.Count(p =>
+                p.Kind == DecisionSignalKind.InformationalEvent
+                && p.Payload != null
+                && p.Payload.TryGetValue(SignalPayloadKeys.EventType, out var et)
+                && et == Constants.EventTypes.SessionStalled);
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/WindowsUpdateClassifierTests.cs

@@ -0,0 +1,85 @@
+#nullable enable
+using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
+using Xunit;
+
+namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
+{
+    /// <summary>
+    /// WindowsUpdateClassifier (D-310) — decides which Windows Update client events are listed one
+    /// by one (OS updates) and which are only counted (Store, Defender, everything else). The
+    /// titles are the shapes the WU client writes on Windows 11 GA and Insider builds.
+    /// </summary>
+    public sealed class WindowsUpdateClassifierTests
+    {
+        [Theory]
+        [InlineData("2026-09 Cumulative Update for Windows 11, version 25H2 for x64-based Systems (KB5099999)")]
+        [InlineData("2026-09 Cumulative Update Preview for Windows 11, version 24H2 for x64-based Systems (KB5099998)")]
+        [InlineData("2026-09 Dynamic Update for Windows 11, version 25H2 for x64-based Systems (KB5099997)")]
+        [InlineData("2026-09 Servicing Stack Update for Windows 11, version 25H2 for x64-based Systems (KB5099996)")]
+        [InlineData("Windows 11 Insider Preview Quality Update (26220.9568)")]
+        [InlineData("Windows 11 Insider Preview Feature Update (26220.9022)")]
+        [InlineData("Windows 11, version 25H2 Upgrade")]
+        [InlineData("2026-09 .NET Framework Security Update (KB5099995)")]
+        [InlineData("2026-08 .NET Framework Preview Update (KB5099994)")]
+        [InlineData("Windows Malicious Software Removal Tool x64 - v5.145 (KB890830)")]
+        public void WindowsAndDotNetFrameworkUpdates_AreOs(string title)
+        {
+            Assert.Equal(WindowsUpdateClassifier.Os, WindowsUpdateClassifier.Classify(title, serviceGuid: null));
+        }
+
+        [Theory]
+        [InlineData("Security Intelligence Update for Microsoft Defender Antivirus - KB2267602 (Version 1.459.505.0) - Current Channel (Broad)")]
+        [InlineData("Update for Microsoft Defender Antivirus antimalware platform - KB4052623 (Version 4.18.26080.4) - Current Channel (Staged)")]
+        // Names "Windows" and "Update" — Defender must still win.
+        [InlineData("Windows 10/11 - Update for Microsoft Defender for Endpoint - KB5005292 (Version 10.8838.26060.15013) - Current Channel (Staged)")]
+        public void DefenderUpdates_AreDefender(string title)
+        {
+            Assert.Equal(WindowsUpdateClassifier.Defender, WindowsUpdateClassifier.Classify(title, serviceGuid: null));
+        }
+
+        [Theory]
+        [InlineData("9NSTH9KHZDLQ-Microsoft.UI.Xaml.2.8")]
+        [InlineData("9NBLGGH4NNS1-Microsoft.DesktopAppInstaller")]
+        // Upper-case "WINDOWS" inside the package name must not make it an OS update.
+        [InlineData("9WZDNCRFHVN5-MICROSOFT.WINDOWSCALCULATOR")]
+        [InlineData("9WZDNCRFHWKN-MICROSOFT.WINDOWSSOUNDRECORDER")]
+        [InlineData("ApplicationSet-9WZDNCRFJ3Q2-Microsoft.BingWeather")]
+        public void StoreProductTitles_AreStore(string title)
+        {
+            Assert.Equal(WindowsUpdateClassifier.Store, WindowsUpdateClassifier.Classify(title, serviceGuid: null));
+        }
+
+        [Theory]
+        [InlineData("{855e8a7c-ecb4-4ca3-b045-1dfa50104289}")]
+        [InlineData("{855E8A7C-ECB4-4CA3-B045-1DFA50104289}")]
+        [InlineData("855e8a7c-ecb4-4ca3-b045-1dfa50104289")]
+        public void StoreServiceGuid_IsStore_WhateverTheTitle(string serviceGuid)
+        {
+            Assert.Equal(WindowsUpdateClassifier.Store,
+                WindowsUpdateClassifier.Classify("2026-09 Cumulative Update for Windows 11 (KB5099999)", serviceGuid));
+        }
+
+        [Fact]
+        public void OtherServiceGuid_LeavesTheTitleInCharge()
+        {
+            Assert.Equal(WindowsUpdateClassifier.Os,
+                WindowsUpdateClassifier.Classify("2026-09 Cumulative Update for Windows 11 (KB5099999)", "{7971f918-a847-4430-9279-4a52d1efe18d}"));
+        }
+
+        [Theory]
+        [InlineData("Intel net Driver Update (24.50.0.4)")]
+        [InlineData("PowerShell v7.6.6 (x64)")]
+        [InlineData("Remote help 5.2.1040.0")]
+        [InlineData("Microsoft Edge-Stable Channel Version 140 Update for x64 based Edge-Chromium (Build 140.0.3485.54)")]
+        [InlineData("Microsoft .NET 8.0.20 Security Update for x64 Client (KB5099993)")]
+        [InlineData("Windows Feature Experience Pack 1000.26100.234.0")]
+        [InlineData("KB5099999")]
+        [InlineData("")]
+        [InlineData("   ")]
+        [InlineData(null)]
+        public void EverythingElse_IsOther(string? title)
+        {
+            Assert.Equal(WindowsUpdateClassifier.Other, WindowsUpdateClassifier.Classify(title!, serviceGuid: null));
+        }
+    }
+}

src/Agent/AutopilotMonitor.Agent.V2.Core.Tests/Monitoring/SystemSignals/WindowsUpdateTrackerTests.cs

@@ -1,6 +1,7 @@
 #nullable enable
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Linq;
 using AutopilotMonitor.Agent.V2.Core.Logging;
 using AutopilotMonitor.Agent.V2.Core.Monitoring.Enrollment.SystemSignals;
@@ -9,55 +10,81 @@ using AutopilotMonitor.Agent.V2.Core.Tests.Harness;
 using AutopilotMonitor.Agent.V2.Core.Tests.Orchestration;
 using AutopilotMonitor.DecisionCore.Engine;
 using AutopilotMonitor.DecisionCore.Signals;
+using AutopilotMonitor.DecisionCore.State;
 using AutopilotMonitor.Shared;
+using Newtonsoft.Json.Linq;
 using Xunit;
 
 namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
 {
     /// <summary>
     /// WindowsUpdateTracker — surfaces quality/cumulative update activity during OOBE from the
-    /// WindowsUpdateClient/Operational channel. Drives the primitive <see cref="WindowsUpdateTracker.ProcessEvent"/>
+    /// WindowsUpdateClient provider: install events from the System log, scan/download events from
+    /// the Operational channel (D-310). Drives the primitive <see cref="WindowsUpdateTracker.ProcessEvent"/>
     /// test seam (no real EventRecord, which is abstract + Windows-only), mirroring the
-    /// ModernDeploymentTracker test pattern.
+    /// ModernDeploymentTracker test pattern. Update titles are the shapes the provider writes.
     /// </summary>
     public sealed class WindowsUpdateTrackerTests : IDisposable
     {
         private static readonly DateTime At = new DateTime(2026, 7, 8, 10, 15, 0, DateTimeKind.Utc);
 
+        private const string Lcu = "2026-09 Cumulative Update for Windows 11, version 25H2 for x64-based Systems (KB5099999)";
+        private const string StoreApp = "9WZDNCRFHVN5-MICROSOFT.WINDOWSCALCULATOR";
+        private const string DefenderIntelligence = "Security Intelligence Update for Microsoft Defender Antivirus - KB2267602 (Version 1.459.505.0) - Current Channel (Broad)";
+
         private readonly TempDirectory _tmp = new TempDirectory();
-        private readonly FakeSignalIngressSink _sink;
-        private readonly WindowsUpdateTracker _tracker;
+        private readonly FakeSignalIngressSink _sink = new FakeSignalIngressSink();
+        private readonly UpdateActivityTally _tally = new UpdateActivityTally();
+        private readonly List<(string Step, string Update, DateTime At)> _osActivity = new List<(string, string, DateTime)>();
+        private readonly WindowsUpdateTracker _system;
+        private readonly WindowsUpdateTracker _operational;
         private long _nextRecordId = 1;
 
         public WindowsUpdateTrackerTests()
         {
-            _sink = new FakeSignalIngressSink();
-            var post = new InformationalEventPost(_sink, new VirtualClock(At));
-            var logger = new AgentLogger(_tmp.Path, AgentLogLevel.Info);
-            _tracker = new WindowsUpdateTracker(
-                sessionId: "sess-wu",
-                tenantId: "tenant-wu",
-                post: post,
-                logger: logger,
-                backfillEnabled: false,
-                stateDirectory: null); // in-memory dedup for most tests
+            // In-memory dedup for most tests.
+            _system = NewTracker(WindowsUpdateTracker.SystemChannel, stateDirectory: null);
+            _operational = NewTracker(channel: null, stateDirectory: null);
         }
 
         public void Dispose() => _tmp.Dispose();
 
-        private void Emit(int eventId, string? errorCode = null, string? updateTitle = "Cumulative Update KB5099999", long? recordId = null)
+        private WindowsUpdateTracker NewTracker(string? channel, string? stateDirectory) =>
+            new WindowsUpdateTracker(
+                sessionId: "sess-wu",
+                tenantId: "tenant-wu",
+                post: new InformationalEventPost(_sink, new VirtualClock(At)),
+                logger: new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                backfillEnabled: false,
+                stateDirectory: stateDirectory,
+                channel: channel,
+                tally: _tally,
+                onOsUpdateActivity: (step, update, at) => _osActivity.Add((step, update, at)));
+
+        private void Emit(
+            WindowsUpdateTracker tracker,
+            int eventId,
+            string? updateTitle = Lcu,
+            string? errorCode = null,
+            long? recordId = null,
+            string? serviceGuid = null,
+            string? updateCount = null,
+            DateTime? at = null,
+            bool isBackfill = false)
         {
-            _tracker.ProcessEvent(
+            tracker.ProcessEvent(
                 eventId: eventId,
                 level: 4,
                 recordId: recordId ?? _nextRecordId++,
-                timeCreatedUtc: At,
+                timeCreatedUtc: at ?? At,
                 updateTitle: updateTitle,
                 updateGuid: "{8b1c8726-1111-2222-3333-444455556666}",
                 updateRevisionNumber: "200",
                 errorCode: errorCode,
                 formattedDescription: null,
-                isBackfill: false);
+                isBackfill: isBackfill,
+                serviceGuid: serviceGuid,
+                updateCount: updateCount);
         }
 
         private IReadOnlyList<FakeSignalIngressSink.PostedSignal> ByType(string eventType) =>
@@ -70,10 +97,17 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
         private static IReadOnlyDictionary<string, object> Data(FakeSignalIngressSink.PostedSignal s) =>
             (IReadOnlyDictionary<string, object>)s.TypedPayload!;
 
+        private int Counted(string key) =>
+            _tally.Snapshot().Where(kv => kv.Key == key).Select(kv => kv.Value).SingleOrDefault();
+
+        // ---------------------------------------------------------------------------
+        // Install events (System log)
+        // ---------------------------------------------------------------------------
+
         [Fact]
         public void FailureEvent_EmitsWindowsUpdateFailed_WithDecodedHResult_AndImmediateUpload()
         {
-            Emit(WindowsUpdateTracker.EventId_InstallFailure, errorCode: "0x80240022");
+            Emit(_system, WindowsUpdateTracker.EventId_InstallFailure, errorCode: "0x80240022");
 
             var failed = ByType(Constants.EventTypes.WindowsUpdateFailed);
             var s = Assert.Single(failed);
@@ -83,37 +117,44 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             var data = Data(s);
             Assert.Equal("0x80240022", data["hresult"]);
             Assert.Equal("WU_E_ALL_UPDATES_FAILED", data["hresultSymbol"]);
-            Assert.Equal("Cumulative Update KB5099999", data["updateTitle"]);
+            Assert.Equal(Lcu, data["updateTitle"]);
             Assert.Equal(20, data["wuEventId"]);
+            Assert.Equal("system", data["wuChannel"]);
+            Assert.Equal("install", data["wuPhase"]);
+            Assert.Equal(WindowsUpdateClassifier.Os, data["updateClass"]);
         }
 
         [Fact]
         public void SuccessEvent_EmitsWindowsUpdateSucceeded_InfoSeverity()
         {
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess);
 
             var ok = ByType(Constants.EventTypes.WindowsUpdateSucceeded);
             var s = Assert.Single(ok);
             Assert.Equal("Info", s.Payload![SignalPayloadKeys.Severity]);
             Assert.Equal("false", s.Payload![SignalPayloadKeys.ImmediateUpload]);
+            Assert.Equal("installed", Data(s)["wuPhase"]);
         }
 
         [Fact]
-        public void StartedAndDownloadEvents_EmitDebugStarted()
+        public void StartedAndDownloadEvents_EmitInfoStarted_WithTheirPhase()
         {
-            Emit(WindowsUpdateTracker.EventId_InstallStarted);
-            Emit(WindowsUpdateTracker.EventId_DownloadStarted);
+            // Info, not Debug: with only OS updates listed they are the visible progress of a
+            // long OOBE update.
+            Emit(_system, WindowsUpdateTracker.EventId_InstallStarted);
+            Emit(_system, WindowsUpdateTracker.EventId_DownloadStarted);
 
             var started = ByType(Constants.EventTypes.WindowsUpdateStarted);
             Assert.Equal(2, started.Count);
-            Assert.All(started, s => Assert.Equal("Debug", s.Payload![SignalPayloadKeys.Severity]));
+            Assert.All(started, s => Assert.Equal("Info", s.Payload![SignalPayloadKeys.Severity]));
+            Assert.Equal(new[] { "install", "download" }, started.Select(s => (string)Data(s)["wuPhase"]).ToArray());
         }
 
         [Fact]
         public void SameRecordId_ProcessedTwice_EmitsOnce()
         {
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess, recordId: 42);
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess, recordId: 42);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 42);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 42);
 
             Assert.Single(ByType(Constants.EventTypes.WindowsUpdateSucceeded));
         }
@@ -125,8 +166,8 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             // with a higher RecordId can be processed first. An older, never-emitted backfill event
             // (lower RecordId) must NOT be suppressed as "already processed" — these early pre-agent
             // OOBE updates are the whole point of the feature. A high-water-mark dedup dropped them.
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess, recordId: 100); // live, high RecordId
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess, recordId: 50);  // backfill, older, never seen
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 100); // live, high RecordId
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 50);  // backfill, older, never seen
 
             Assert.Equal(2, ByType(Constants.EventTypes.WindowsUpdateSucceeded).Count);
         }
@@ -138,53 +179,212 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             // time, not at agent start (the ctor's default UtcNow). InformationalEventPost forwards
             // EnrollmentEvent.Timestamp as the signal's OccurredAtUtc, which drives the timeline entry.
             var eventTime = new DateTime(2026, 7, 8, 7, 5, 0, DateTimeKind.Utc); // well before `At`
-            _tracker.ProcessEvent(
-                eventId: WindowsUpdateTracker.EventId_InstallFailure,
-                level: 4,
-                recordId: 7,
-                timeCreatedUtc: eventTime,
-                updateTitle: "KB5099999",
-                updateGuid: null,
-                updateRevisionNumber: null,
-                errorCode: "0x80240022",
-                formattedDescription: null,
-                isBackfill: true);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallFailure, errorCode: "0x80240022",
+                recordId: 7, at: eventTime, isBackfill: true);
 
             var s = Assert.Single(ByType(Constants.EventTypes.WindowsUpdateFailed));
             Assert.Equal(eventTime, s.OccurredAtUtc);
+            Assert.Equal(true, Data(s)["backfilled"]);
         }
 
         [Fact]
         public void NegativeRecordId_IsNeverDeduped()
         {
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess, recordId: -1);
-            Emit(WindowsUpdateTracker.EventId_InstallSuccess, recordId: -1);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: -1);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: -1);
 
             Assert.Equal(2, ByType(Constants.EventTypes.WindowsUpdateSucceeded).Count);
         }
 
+        // ---------------------------------------------------------------------------
+        // Scan/download events (Operational channel)
+        // ---------------------------------------------------------------------------
+
         [Fact]
-        public void Watermark_PersistsAcrossTrackerInstances()
+        public void Downloaded_EmitsInfoStarted_WithDownloadedPhase()
         {
-            var post = new InformationalEventPost(_sink, new VirtualClock(At));
-            var logger = new AgentLogger(_tmp.Path, AgentLogLevel.Info);
+            Emit(_operational, WindowsUpdateTracker.EventId_Downloaded);
 
-            var first = new WindowsUpdateTracker("s", "t", post, logger, backfillEnabled: false, stateDirectory: _tmp.Path);
-            first.ProcessEvent(WindowsUpdateTracker.EventId_InstallSuccess, 4, recordId: 500, timeCreatedUtc: At,
-                updateTitle: "KB1", updateGuid: null, updateRevisionNumber: null, errorCode: null,
-                formattedDescription: null, isBackfill: false);
+            var s = Assert.Single(ByType(Constants.EventTypes.WindowsUpdateStarted));
+            Assert.Equal("Info", s.Payload![SignalPayloadKeys.Severity]);
+            Assert.Equal("downloaded", Data(s)["wuPhase"]);
+            Assert.Equal("operational", Data(s)["wuChannel"]);
+        }
 
-            // A fresh tracker (simulating an agent restart) must load the watermark and skip the
-            // already-emitted record when the OOBE backfill re-reads it.
-            var second = new WindowsUpdateTracker("s", "t", post, logger, backfillEnabled: false, stateDirectory: _tmp.Path);
-            second.LoadWatermark();
-            second.ProcessEvent(WindowsUpdateTracker.EventId_InstallSuccess, 4, recordId: 500, timeCreatedUtc: At,
-                updateTitle: "KB1", updateGuid: null, updateRevisionNumber: null, errorCode: null,
-                formattedDescription: null, isBackfill: true);
+        [Fact]
+        public void DownloadFailure_OfAnOsUpdate_EmitsWarning_WithDownloadPhase()
+        {
+            Emit(_operational, WindowsUpdateTracker.EventId_DownloadFailed, errorCode: "0x80248007");
+
+            var s = Assert.Single(ByType(Constants.EventTypes.WindowsUpdateFailed));
+            Assert.Equal("Warning", s.Payload![SignalPayloadKeys.Severity]);
+            Assert.Equal("false", s.Payload![SignalPayloadKeys.ImmediateUpload]);
+            var data = Data(s);
+            Assert.Equal("download", data["wuPhase"]);
+            Assert.Equal("0x80248007", data["hresult"]);
+        }
+
+        [Fact]
+        public void ScanFound_EmitsOnlyChangedCounts_AndCountsTheRepeats()
+        {
+            foreach (var count in new[] { "3", "3", "5", "5", "0" })
+                Emit(_operational, WindowsUpdateTracker.EventId_ScanFound, updateTitle: null, updateCount: count);
+
+            var found = ByType(Constants.EventTypes.WindowsUpdateStarted);
+            Assert.Equal(new[] { "3", "5", "0" }, found.Select(s => (string)Data(s)["updateCount"]).ToArray());
+            Assert.All(found, s => Assert.Equal("Debug", s.Payload![SignalPayloadKeys.Severity]));
+            Assert.All(found, s => Assert.Equal("scan", Data(s)["wuPhase"]));
+            Assert.All(found, s => Assert.False(Data(s).ContainsKey("updateClass")));
+            Assert.Contains("scan found 3 update(s)", found[0].Payload![SignalPayloadKeys.Message]);
+            Assert.Equal(2, Counted("scan_found_repeat"));
+            Assert.Empty(_osActivity); // a scan result is not an update step
+        }
+
+        [Fact]
+        public void ScanFound_IsCappedPerRun()
+        {
+            for (var i = 0; i < WindowsUpdateTracker.MaxScanFoundEmissions + 2; i++)
+                Emit(_operational, WindowsUpdateTracker.EventId_ScanFound, updateTitle: null, updateCount: i.ToString());
+
+            Assert.Equal(WindowsUpdateTracker.MaxScanFoundEmissions, ByType(Constants.EventTypes.WindowsUpdateStarted).Count);
+            Assert.Equal(2, Counted("scan_found_repeat"));
+        }
+
+        [Fact]
+        public void ScanFailed_EmitsEachErrorCodeOnce()
+        {
+            Emit(_operational, WindowsUpdateTracker.EventId_ScanFailed, updateTitle: null, errorCode: "0x8024401c");
+            Emit(_operational, WindowsUpdateTracker.EventId_ScanFailed, updateTitle: null, errorCode: "0x8024401c");
+            Emit(_operational, WindowsUpdateTracker.EventId_ScanFailed, updateTitle: null, errorCode: "0x80072EE2");
+            Emit(_operational, WindowsUpdateTracker.EventId_ScanFailed, updateTitle: null, errorCode: "0x8024401C");
+
+            var failed = ByType(Constants.EventTypes.WindowsUpdateFailed);
+            Assert.Equal(2, failed.Count);
+            Assert.All(failed, s => Assert.Equal("Warning", s.Payload![SignalPayloadKeys.Severity]));
+            Assert.All(failed, s => Assert.Equal("scan", Data(s)["wuPhase"]));
+            Assert.Equal(2, Counted("scan_failed_repeat"));
+            Assert.Empty(_osActivity);
+        }
+
+        [Fact]
+        public void ScanFailed_IsCappedPerRun()
+        {
+            for (var i = 0; i < WindowsUpdateTracker.MaxScanFailedEmissions + 2; i++)
+                Emit(_operational, WindowsUpdateTracker.EventId_ScanFailed, updateTitle: null, errorCode: $"0x8024000{i}");
+
+            Assert.Equal(WindowsUpdateTracker.MaxScanFailedEmissions, ByType(Constants.EventTypes.WindowsUpdateFailed).Count);
+            Assert.Equal(2, Counted("scan_failed_repeat"));
+        }
+
+        // ---------------------------------------------------------------------------
+        // Classification — only OS updates are listed, the rest is counted
+        // ---------------------------------------------------------------------------
+
+        [Theory]
+        [InlineData(StoreApp, null, WindowsUpdateTracker.EventId_InstallSuccess, "store_19")]
+        [InlineData("Some App", "{855e8a7c-ecb4-4ca3-b045-1dfa50104289}", WindowsUpdateTracker.EventId_Downloaded, "store_41")]
+        [InlineData(DefenderIntelligence, null, WindowsUpdateTracker.EventId_InstallStarted, "defender_43")]
+        [InlineData("Intel net Driver Update (24.50.0.4)", null, WindowsUpdateTracker.EventId_DownloadStarted, "other_44")]
+        // A real download failure names no update at all; it must not reach ANALYZE-DEV-004 as
+        // a failed OS update.
+        [InlineData("", null, WindowsUpdateTracker.EventId_DownloadFailed, "other_31")]
+        [InlineData("Some App", "{855e8a7c-ecb4-4ca3-b045-1dfa50104289}", WindowsUpdateTracker.EventId_InstallFailure, "store_20")]
+        public void NonOsUpdates_AreCountedNotEmitted(string title, string? serviceGuid, int eventId, string expectedKey)
+        {
+            var tracker = WindowsUpdateTracker.IsSystemChannelEventId(eventId) ? _system : _operational;
+            Emit(tracker, eventId, updateTitle: title, serviceGuid: serviceGuid, errorCode: "0x80248007");
+
+            Assert.Empty(_sink.Posted);
+            Assert.Empty(_osActivity);
+            Assert.Equal(1, Counted(expectedKey));
+            // The census still sees the channel working.
+            Assert.Equal(1, tracker.EmittedThisRun);
+        }
+
+        [Fact]
+        public void CountedRecord_DeliveredTwice_IsCountedOnce()
+        {
+            // Live watcher and backfill overlap: the seen-set dedups counted records too.
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, updateTitle: StoreApp, recordId: 7);
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, updateTitle: StoreApp, recordId: 7);
+
+            Assert.Equal(1, Counted("store_19"));
+        }
+
+        [Fact]
+        public void OsUpdateSteps_AreReportedToTheEngineCallback()
+        {
+            var t0 = At;
+            Emit(_system, WindowsUpdateTracker.EventId_DownloadStarted, at: t0);
+            Emit(_operational, WindowsUpdateTracker.EventId_Downloaded, at: t0.AddMinutes(4));
+            Emit(_system, WindowsUpdateTracker.EventId_InstallStarted, at: t0.AddMinutes(5));
+            Emit(_system, WindowsUpdateTracker.EventId_InstallSuccess, at: t0.AddMinutes(31));
+            Emit(_system, WindowsUpdateTracker.EventId_InstallFailure, errorCode: "0x800F0922", at: t0.AddMinutes(32));
+            Emit(_operational, WindowsUpdateTracker.EventId_DownloadFailed, errorCode: "0x80248007", at: t0.AddMinutes(33));
+
+            Assert.Equal(
+                new[]
+                {
+                    OsUpdateSteps.DownloadStarted, OsUpdateSteps.Downloaded, OsUpdateSteps.InstallStarted,
+                    OsUpdateSteps.Installed, OsUpdateSteps.Failed, OsUpdateSteps.Failed,
+                },
+                _osActivity.Select(a => a.Step).ToArray());
+            Assert.All(_osActivity, a => Assert.Equal(Lcu, a.Update));
+            Assert.Equal(t0.AddMinutes(31), _osActivity[3].At);
+        }
+
+        [Fact]
+        public void ThrowingCallback_NeverCostsTheEvent()
+        {
+            var tracker = new WindowsUpdateTracker(
+                "s", "t", new InformationalEventPost(_sink, new VirtualClock(At)),
+                new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                backfillEnabled: false,
+                channel: WindowsUpdateTracker.SystemChannel,
+                onOsUpdateActivity: (step, update, at) => throw new InvalidOperationException("boom"));
+
+            Emit(tracker, WindowsUpdateTracker.EventId_InstallSuccess);
 
             Assert.Single(ByType(Constants.EventTypes.WindowsUpdateSucceeded));
         }
 
+        // ---------------------------------------------------------------------------
+        // Channels and XPath
+        // ---------------------------------------------------------------------------
+
+        [Fact]
+        public void DefaultEventIds_FollowTheProviderManifest()
+        {
+            Assert.Equal(WindowsUpdateTracker.SystemChannel, _system.WatchedChannel);
+            Assert.Equal(new[] { 19, 20, 43, 44 }, _system.TargetedEventIds.OrderBy(id => id).ToArray());
+            Assert.Equal(WindowsUpdateTracker.Channel, _operational.WatchedChannel);
+            Assert.Equal(new[] { 25, 26, 31, 41 }, _operational.TargetedEventIds.OrderBy(id => id).ToArray());
+        }
+
+        [Theory]
+        [InlineData(16, true)]
+        [InlineData(19, true)]
+        [InlineData(20, true)]
+        [InlineData(24, true)]
+        [InlineData(27, true)]
+        [InlineData(28, true)]
+        [InlineData(32, true)]
+        [InlineData(33, true)]
+        [InlineData(43, true)]
+        [InlineData(44, true)]
+        [InlineData(212, true)]
+        [InlineData(218, true)]
+        [InlineData(25, false)]
+        [InlineData(26, false)]
+        [InlineData(31, false)]
+        [InlineData(41, false)]
+        [InlineData(15, false)]
+        [InlineData(219, false)]
+        public void IsSystemChannelEventId_MatchesTheManifest(int eventId, bool expected)
+        {
+            Assert.Equal(expected, WindowsUpdateTracker.IsSystemChannelEventId(eventId));
+        }
+
         [Fact]
         public void BuildXPath_ContainsAllTargetedIds_Ordered()
         {
@@ -192,6 +392,113 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             Assert.Equal("*[System[(EventID=19 or EventID=20 or EventID=43 or EventID=44)]]", xpath);
         }
 
+        [Fact]
+        public void BuildXPath_SharedSystemLog_FiltersTheProvider_AndTheLookback()
+        {
+            // Verified against a real System log: the provider clause keeps the other providers'
+            // EventIDs 19/20/43/44 out of the shared channel.
+            var ids = new HashSet<int> { 44, 19, 20, 43 };
+
+            Assert.Equal(
+                "*[System[Provider[@Name='Microsoft-Windows-WindowsUpdateClient'] and (EventID=19 or EventID=20 or EventID=43 or EventID=44)]]",
+                WindowsUpdateTracker.BuildXPath(ids, WindowsUpdateTracker.ProviderName));
+            Assert.Equal(
+                "*[System[Provider[@Name='Microsoft-Windows-WindowsUpdateClient'] and (EventID=19 or EventID=20 or EventID=43 or EventID=44) and TimeCreated[timediff(@SystemTime) <= 3600000]]]",
+                WindowsUpdateTracker.BuildXPath(ids, WindowsUpdateTracker.ProviderName, lookbackMs: 3600000));
+            Assert.Equal(
+                "*[System[(EventID=25 or EventID=26) and TimeCreated[timediff(@SystemTime) <= 60000]]]",
+                WindowsUpdateTracker.BuildXPath(new HashSet<int> { 26, 25 }, providerName: null, lookbackMs: 60000));
+        }
+
+        // ---------------------------------------------------------------------------
+        // Watermark
+        // ---------------------------------------------------------------------------
+
+        [Fact]
+        public void Watermark_PersistsAcrossTrackerInstances()
+        {
+            var first = NewTracker(WindowsUpdateTracker.SystemChannel, _tmp.Path);
+            Emit(first, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 500);
+
+            // A fresh tracker (simulating an agent restart) must load the watermark and skip the
+            // already-emitted record when the OOBE backfill re-reads it.
+            var second = NewTracker(WindowsUpdateTracker.SystemChannel, _tmp.Path);
+            second.LoadWatermark();
+            Emit(second, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 500, isBackfill: true);
+
+            Assert.Single(ByType(Constants.EventTypes.WindowsUpdateSucceeded));
+        }
+
+        [Fact]
+        public void Watermark_IsPerChannel()
+        {
+            // RecordIds are per channel: System record 500 and Operational record 500 are two
+            // different events and must not dedup each other — before or after a restart.
+            Emit(NewTracker(WindowsUpdateTracker.SystemChannel, _tmp.Path), WindowsUpdateTracker.EventId_InstallSuccess, recordId: 500);
+            Emit(NewTracker(null, _tmp.Path), WindowsUpdateTracker.EventId_Downloaded, recordId: 500);
+
+            Assert.Single(ByType(Constants.EventTypes.WindowsUpdateSucceeded));
+            Assert.Single(ByType(Constants.EventTypes.WindowsUpdateStarted));
+            Assert.Equal(500L, ReadWatermark(WindowsUpdateTracker.SystemWatermarkStateFileName));
+            Assert.Equal(500L, ReadWatermark(WindowsUpdateTracker.WatermarkStateFileName));
+
+            var system = NewTracker(WindowsUpdateTracker.SystemChannel, _tmp.Path);
+            var operational = NewTracker(null, _tmp.Path);
+            system.LoadWatermark();
+            operational.LoadWatermark();
+            Emit(system, WindowsUpdateTracker.EventId_InstallSuccess, recordId: 500, isBackfill: true);
+            Emit(operational, WindowsUpdateTracker.EventId_Downloaded, recordId: 500, isBackfill: true);
+
+            Assert.Single(ByType(Constants.EventTypes.WindowsUpdateSucceeded));
+            Assert.Single(ByType(Constants.EventTypes.WindowsUpdateStarted));
+        }
+
+        [Fact]
+        public void CountedRecords_WriteNoStateFile()
+        {
+            // A Store/Defender burst must not cost a state-file write per record; only emitted
+            // records move the persisted watermark.
+            var tracker = NewTracker(WindowsUpdateTracker.SystemChannel, _tmp.Path);
+            Emit(tracker, WindowsUpdateTracker.EventId_InstallSuccess, updateTitle: StoreApp, recordId: 600);
+            Emit(tracker, WindowsUpdateTracker.EventId_InstallStarted, updateTitle: DefenderIntelligence, recordId: 601);
+
+            Assert.False(File.Exists(Path.Combine(_tmp.Path, WindowsUpdateTracker.SystemWatermarkStateFileName)));
+
+            Emit(tracker, WindowsUpdateTracker.EventId_InstallStarted, recordId: 602);
+            Assert.Equal(602L, ReadWatermark(WindowsUpdateTracker.SystemWatermarkStateFileName));
+        }
+
+        [Fact]
+        public void Watermark_PersistsOnlyAfterTheEngineSignalWasHandedOver()
+        {
+            // A restart's backfill skips a persisted record, so the record's engine signal must be
+            // on its way before the watermark reaches the disk — never the other way round.
+            var path = Path.Combine(_tmp.Path, WindowsUpdateTracker.SystemWatermarkStateFileName);
+            bool? watermarkOnDiskAtSignal = null;
+            var tracker = new WindowsUpdateTracker(
+                sessionId: "sess-wu",
+                tenantId: "tenant-wu",
+                post: new InformationalEventPost(_sink, new VirtualClock(At)),
+                logger: new AgentLogger(_tmp.Path, AgentLogLevel.Info),
+                backfillEnabled: false,
+                stateDirectory: _tmp.Path,
+                channel: WindowsUpdateTracker.SystemChannel,
+                tally: _tally,
+                onOsUpdateActivity: (step, update, at) => watermarkOnDiskAtSignal = File.Exists(path));
+
+            Emit(tracker, WindowsUpdateTracker.EventId_InstallStarted, recordId: 700);
+
+            Assert.False(watermarkOnDiskAtSignal);
+            Assert.Equal(700L, ReadWatermark(WindowsUpdateTracker.SystemWatermarkStateFileName));
+        }
+
+        private long ReadWatermark(string fileName) =>
+            JObject.Parse(File.ReadAllText(Path.Combine(_tmp.Path, fileName)))["LastRecordId"]!.Value<long>();
+
+        // ---------------------------------------------------------------------------
+        // Parsing and HRESULT decoding
+        // ---------------------------------------------------------------------------
+
         [Fact]
         public void ParseEventData_ExtractsNamedFields_NamespaceAgnostic()
         {
@@ -212,6 +519,24 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             Assert.True(data.ContainsKey("UPDATETITLE"));
         }
 
+        [Fact]
+        public void ParseEventData_ReadsTheScanFields()
+        {
+            // Event 26 (scan found N) and 25 (scan failed) carry no update title.
+            const string xml =
+                "<Event xmlns='http://schemas.microsoft.com/win/2004/08/events/event'>" +
+                "<System><EventID>26</EventID></System>" +
+                "<EventData>" +
+                "<Data Name='updateCount'>3</Data>" +
+                "<Data Name='serviceGuid'>{8b24b027-1dee-babb-9a95-3517dfb9c552}</Data>" +
+                "</EventData></Event>";
+
+            var data = WindowsUpdateTracker.ParseEventData(xml);
+            Assert.Equal("3", data["updateCount"]);
+            Assert.Equal("{8b24b027-1dee-babb-9a95-3517dfb9c552}", data["serviceGuid"]);
+            Assert.False(data.ContainsKey("updateTitle"));
+        }
+
         [Fact]
         public void ParseEventData_MalformedXml_ReturnsEmpty_NeverThrows()
         {
@@ -303,10 +628,23 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
             var data = Data(s);
             Assert.Equal("21=1,25=3", data["wuClientCensus"]);
             Assert.Equal("200=2", data["updateOrchestratorCensus"]);
-            Assert.Equal("19,20,43,44", data["targetedEventIds"]);
+            Assert.Equal("25,26,31,41", data["targetedEventIds"]);
             Assert.False(data.ContainsKey("censusTruncated"));
         }
 
+        [Fact]
+        public void Census_ListsTheTargetedIdsOfEveryChannel()
+        {
+            // The host runs the census on the Operational instance; the evidence must still say
+            // the System-log install IDs were watched too.
+            var tracker = BuildCensusTracker(censusEnabled: true, osBuildChanged: true);
+
+            tracker.EmitChannelCensusIfBlind(otherChannelsEmitted: 0, otherTargetedEventIds: new[] { 44, 19, 20, 43 });
+
+            var s = Assert.Single(ByType(Constants.EventTypes.WindowsUpdateChannelCensus));
+            Assert.Equal("19,20,25,26,31,41,43,44", Data(s)["targetedEventIds"]);
+        }
+
         [Fact]
         public void Census_BuildUnchanged_EmitsNothing()
         {
@@ -320,17 +658,27 @@ namespace AutopilotMonitor.Agent.V2.Core.Tests.Monitoring.SystemSignals
         [Fact]
         public void Census_TargetedEventsWereEmittedThisRun_EmitsNothing()
         {
-            // The watcher captured the update through its normal path — no blind spot to report.
+            // The watcher captured activity through its normal path — no blind spot to report.
+            // Any class counts: a counted Store update proves the channel is read as well.
             var tracker = BuildCensusTracker(censusEnabled: true, osBuildChanged: true);
-            tracker.ProcessEvent(WindowsUpdateTracker.EventId_InstallSuccess, 4, recordId: 9, timeCreatedUtc: At,
-                updateTitle: "KB1", updateGuid: null, updateRevisionNumber: null, errorCode: null,
-                formattedDescription: null, isBackfill: false);
+            Emit(tracker, WindowsUpdateTracker.EventId_Downloaded, updateTitle: StoreApp, recordId: 9);
 
             tracker.EmitChannelCensusIfBlind();
 
             Assert.Empty(ByType(Constants.EventTypes.WindowsUpdateChannelCensus));
         }
 
+        [Fact]
+        public void Census_AnotherChannelEmitted_EmitsNothing()
+        {
+            // The System-log watcher saw the install — the update was not missed.
+            var tracker = BuildCensusTracker(censusEnabled: true, osBuildChanged: true);
+
+            tracker.EmitChannelCensusIfBlind(otherChannelsEmitted: 1);
+
+            Assert.Empty(ByType(Constants.EventTypes.WindowsUpdateChannelCensus));
+        }
+
         [Fact]
         public void Census_DisabledByConfig_EmitsNothing()
         {