From dca2517cf04a825f397bb1b894cadb7ed266bd0e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 30 Dec 2025 12:19:35 +0000
Subject: [PATCH] Normalize digit-only KB IDs to include KB prefix

Co-authored-by: Kvarkas <3611964+Kvarkas@users.noreply.github.com>
---
 .../InstalledWindowsUpdateChecker.cs           | 10 ++++++++--
 .../InstalledWindowsUpdateCheckerTests.cs      | 18 ++++++++++++++++--
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/mRemoteNGInstaller/CustomActions/InstalledWindowsUpdateChecker.cs b/mRemoteNGInstaller/CustomActions/InstalledWindowsUpdateChecker.cs
index 48e555be3..6df0d6f4c 100644
--- a/mRemoteNGInstaller/CustomActions/InstalledWindowsUpdateChecker.cs
+++ b/mRemoteNGInstaller/CustomActions/InstalledWindowsUpdateChecker.cs
@@ -94,8 +94,14 @@ namespace CustomActions
             if (!KbPattern.IsMatch(trimmedKb))
                 return string.Empty;
 
-            // Return the sanitized value (uppercased for consistency)
-            return trimmedKb.ToUpperInvariant();
+            // Normalize to uppercase
+            var normalizedKb = trimmedKb.ToUpperInvariant();
+            
+            // Ensure KB prefix is present (Win32_QuickFixEngineering always uses the KB prefix)
+            if (!normalizedKb.StartsWith("KB"))
+                normalizedKb = "KB" + normalizedKb;
+
+            return normalizedKb;
         }
     }
 }
\ No newline at end of file
diff --git a/mRemoteNGTests/Installer/InstalledWindowsUpdateCheckerTests.cs b/mRemoteNGTests/Installer/InstalledWindowsUpdateCheckerTests.cs
index aa47bc791..3be24dfd7 100644
--- a/mRemoteNGTests/Installer/InstalledWindowsUpdateCheckerTests.cs
+++ b/mRemoteNGTests/Installer/InstalledWindowsUpdateCheckerTests.cs
@@ -46,10 +46,10 @@ namespace mRemoteNGTests.Installer
         }
 
         [Test]
-        public void SanitizeKbId_ValidNumberOnly_ReturnsUppercased()
+        public void SanitizeKbId_ValidNumberOnly_ReturnsWithKbPrefix()
         {
             var result = InvokeSanitizeKbId("1234567");
-            Assert.That(result, Is.EqualTo("1234567"));
+            Assert.That(result, Is.EqualTo("KB1234567"));
         }
 
         [Test]
@@ -175,6 +175,20 @@ namespace mRemoteNGTests.Installer
             Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321'"));
         }
 
+        [Test]
+        public void BuildWhereClause_DigitOnlyKb_AddsKbPrefix()
+        {
+            var result = InvokeBuildWhereClause(new[] { "1234567" });
+            Assert.That(result, Is.EqualTo("HotFixID='KB1234567'"));
+        }
+
+        [Test]
+        public void BuildWhereClause_MixedPrefixedAndDigitOnly_NormalizesAll()
+        {
+            var result = InvokeBuildWhereClause(new[] { "1234567", "KB7654321", "kb9999999" });
+            Assert.That(result, Is.EqualTo("HotFixID='KB1234567' OR HotFixID='KB7654321' OR HotFixID='KB9999999'"));
+        }
+
         #endregion
 
         #region Helper Methods