From ac7aabe43b951b1d948fc8d87c293ed6a210c844 Mon Sep 17 00:00:00 2001
From: Oliver Kieselbach <oliver.kieselbach@outlook.com>
Date: Tue, 31 Mar 2026 03:41:22 +0200
Subject: [PATCH] fix ntpserver default

---
 src/Agent/AutopilotMonitor.Agent/buildcounter.txt            | 2 +-
 .../DataAccess/TableStorage/TableConfigRepository.cs         | 2 +-
 tasks/lessons.md                                             | 5 +++++
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/Agent/AutopilotMonitor.Agent/buildcounter.txt b/src/Agent/AutopilotMonitor.Agent/buildcounter.txt
index dc3a10aa..8766d8a9 100644
--- a/src/Agent/AutopilotMonitor.Agent/buildcounter.txt
+++ b/src/Agent/AutopilotMonitor.Agent/buildcounter.txt
@@ -1 +1 @@
-731
+732
diff --git a/src/Backend/AutopilotMonitor.Functions/DataAccess/TableStorage/TableConfigRepository.cs b/src/Backend/AutopilotMonitor.Functions/DataAccess/TableStorage/TableConfigRepository.cs
index bd6ac2ec..94c2855d 100644
--- a/src/Backend/AutopilotMonitor.Functions/DataAccess/TableStorage/TableConfigRepository.cs
+++ b/src/Backend/AutopilotMonitor.Functions/DataAccess/TableStorage/TableConfigRepository.cs
@@ -464,7 +464,7 @@ namespace AutopilotMonitor.Functions.DataAccess.TableStorage
                 RebootDelaySeconds = entity.GetInt32("RebootDelaySeconds"),
                 EnableGeoLocation = entity.GetBoolean("EnableGeoLocation"),
                 EnableTimezoneAutoSet = entity.GetBoolean("EnableTimezoneAutoSet"),
-                NtpServer = entity.GetString("NtpServer") ?? "",
+                NtpServer = entity.GetString("NtpServer") ?? "time.windows.com",
                 EnableImeMatchLog = entity.GetBoolean("EnableImeMatchLog"),
                 LogLevel = entity.GetString("LogLevel"),
                 MaxBatchSize = entity.GetInt32("MaxBatchSize"),
diff --git a/tasks/lessons.md b/tasks/lessons.md
index f980001a..ded00d4b 100644
--- a/tasks/lessons.md
+++ b/tasks/lessons.md
@@ -14,6 +14,11 @@
 
 ## Common Mistakes
 
+### Table Storage mapping defaults must match domain defaults (2026-03-31)
+**What went wrong:** Added `NtpServer` mapping with `?? ""` fallback. Existing tenants had no value stored → got empty string instead of `"time.windows.com"` → agent NTP check broke.
+**Rule:** When adding missing Table Storage read mappings, the `??` fallback MUST match the domain/model default (check `AgentConfigResponse`, `GetAgentConfigFunction`, or the property initializer). Never use empty string as fallback for fields that have a meaningful default.
+**Severity:** PRODUCTION — silently breaks agent functionality for all existing tenants.
+
 ### PowerShell scripts deployed via Intune MUST be pure ASCII (2026-03-30)
 **What went wrong:** Em-dash characters `—` (U+2014) and Unicode symbols (✓, →, ✗) in Bootstrap .ps1 scripts caused cascading PowerShell parse errors in production. The IME (Intune Management Extension) uses PowerShell 5.1 which reads scripts without BOM as ANSI — multi-byte UTF-8 chars get corrupted.
 **Rule:** ALL `.ps1` files under `scripts/Bootstrap/` (and any other scripts deployed via Intune) MUST contain only ASCII characters (0x00-0x7F). No em-dashes, no Unicode symbols, no special quotes. Use `-` instead of `—`, `[OK]` instead of `✓`, etc.