diff --git a/AyCode.Core/Helpers/TaskHelper.cs b/AyCode.Core/Helpers/TaskHelper.cs
index 4cc1ac2..3aa3dbb 100644
--- a/AyCode.Core/Helpers/TaskHelper.cs
+++ b/AyCode.Core/Helpers/TaskHelper.cs
@@ -1,7 +1,27 @@
-namespace AyCode.Core.Helpers
+using System.Runtime.CompilerServices;
+using AyCode.Core.Loggers;
+
+namespace AyCode.Core.Helpers
 {
     public static class TaskHelper
     {
+        /// <summary>
+        /// Optional ambient logger for fire-and-forget faults. Set once at startup (after the DI
+        /// container is built) in each host's entry point, e.g.
+        /// <c>TaskHelper.Logger = new LoggerClient&lt;TaskHelper&gt;(writers);</c>.
+        /// When null, faults are swallowed (legacy behaviour). A per-call <c>logger</c> argument
+        /// passed to any <c>Forget</c> overload overrides this ambient instance.
+        /// </summary>
+        public static IAcLoggerBase? Logger { get; set; }
+
+        /// <summary>
+        /// Logs a fire-and-forget fault. Normal cancellation is filtered out by the callers,
+        /// so anything reaching here is a real fault worth recording. Resolves the logger as
+        /// "explicit per-call argument, else ambient <see cref="Logger"/>"; both null → silent.
+        /// </summary>
+        private static void LogForgetFault(Exception ex, IAcLoggerBase? logger, string caller, int line)
+            => (logger ?? Logger)?.Error($"Fire-and-forget faulted @ {caller}:{line}", ex);
+
         public static bool WaitTo(Func<bool> predicate, int msTimeout = 10000, int msDelay = 5, int msFirstDelay = 0)
             => WaitToAsync(predicate, msTimeout, msDelay, msFirstDelay).GetAwaiter().GetResult();
 
@@ -48,56 +68,68 @@
             return predicate();
         }
 
-        public static void Forget(this Task task)
+        public static void Forget(this Task task, IAcLoggerBase? logger = null, [CallerMemberName] string caller = "", [CallerLineNumber] int line = 0)
         {
-            if (!task.IsCompleted || task.IsFaulted)
-                _ = ForgetAwaited(task);
+            if (!task.IsCompleted || task.IsFaulted) _ = ForgetAwaited(task, logger, caller, line);
+            return;
 
-            static async Task ForgetAwaited(Task task)
+            static async Task ForgetAwaited(Task task, IAcLoggerBase? logger, string caller, int line)
             {
                 try
                 {
                     await task.ConfigureAwait(false);
                 }
-                catch
+                catch (OperationCanceledException)
                 {
-                    // Swallow exception - fire and forget semantics
+                    // Normal cancellation — not a fault.
+                }
+                catch (Exception ex)
+                {
+                    LogForgetFault(ex, logger, caller, line);
                 }
             }
         }
 
-        public static void Forget(this ValueTask task)
+        public static void Forget(this ValueTask task, IAcLoggerBase? logger = null, [CallerMemberName] string caller = "", [CallerLineNumber] int line = 0)
         {
-            if (!task.IsCompleted || task.IsFaulted)
-                _ = ForgetAwaited(task);
+            if (!task.IsCompleted || task.IsFaulted) _ = ForgetAwaited(task, logger, caller, line);
+            return;
 
-            static async Task ForgetAwaited(ValueTask task)
+            static async Task ForgetAwaited(ValueTask task, IAcLoggerBase? logger, string caller, int line)
             {
                 try
                 {
                     await task.ConfigureAwait(false);
                 }
-                catch
+                catch (OperationCanceledException)
                 {
-                    // Swallow exception - fire and forget semantics
+                    // Normal cancellation — not a fault.
+                }
+                catch (Exception ex)
+                {
+                    LogForgetFault(ex, logger, caller, line);
                 }
             }
         }
 
-        public static void Forget<T>(this ValueTask<T> task)
+        public static void Forget<T>(this ValueTask<T> task, IAcLoggerBase? logger = null, [CallerMemberName] string caller = "", [CallerLineNumber] int line = 0)
         {
-            if (!task.IsCompleted || task.IsFaulted)
-                _ = ForgetAwaited(task);
+            if (!task.IsCompleted || task.IsFaulted) _ = ForgetAwaited(task, logger, caller, line);
+            return;
 
-            static async Task ForgetAwaited(ValueTask<T> task)
+            static async Task ForgetAwaited(ValueTask<T> task, IAcLoggerBase? logger, string caller, int line)
             {
                 try
                 {
                     await task.ConfigureAwait(false);
                 }
-                catch
+                catch (OperationCanceledException)
                 {
-                    // Swallow exception - fire and forget semantics
+                    // Normal cancellation — not a fault.
+                }
+                catch (Exception ex)
+                {
+                    LogForgetFault(ex, logger, caller, line);
                 }
             }
         }
diff --git a/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemListDataSource.cs b/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemListDataSource.cs
index 0c0a7b1..e9672e3 100644
--- a/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemListDataSource.cs
+++ b/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemListDataSource.cs
@@ -7,5 +7,5 @@ namespace AyCode.Services.Server.Tests.SignalRs.SignalRDatasources;
 public class TestOrderItemListDataSource : AcSignalRDataSource<TestOrderItem_All_True, int, List<TestOrderItem_All_True>>
 {
     public TestOrderItemListDataSource(AcSignalRClientBase signalRClient, SignalRCrudTags crudTags)
-        : base(signalRClient, crudTags) { }
+        : base(signalRClient, crudTags, null) { }
 }
\ No newline at end of file
diff --git a/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemObservableDataSource.cs b/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemObservableDataSource.cs
index dff2ddf..a9e2c81 100644
--- a/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemObservableDataSource.cs
+++ b/AyCode.Services.Server.Tests/SignalRs/SignalRDatasources/TestOrderItemObservableDataSource.cs
@@ -8,5 +8,5 @@ namespace AyCode.Services.Server.Tests.SignalRs.SignalRDatasources;
 public class TestOrderItemObservableDataSource : AcSignalRDataSource<TestOrderItem_All_True, int, AcObservableCollection<TestOrderItem_All_True>>
 {
     public TestOrderItemObservableDataSource(AcSignalRClientBase signalRClient, SignalRCrudTags crudTags)
-        : base(signalRClient, crudTags) { }
+        : base(signalRClient, crudTags, null) { }
 }
\ No newline at end of file
diff --git a/AyCode.Services.Server/SignalRs/AcSignalRDataSource.cs b/AyCode.Services.Server/SignalRs/AcSignalRDataSource.cs
index 008d2be..c7ffdc3 100644
--- a/AyCode.Services.Server/SignalRs/AcSignalRDataSource.cs
+++ b/AyCode.Services.Server/SignalRs/AcSignalRDataSource.cs
@@ -1,15 +1,17 @@
-using AyCode.Core.Enums;
+using AyCode.Core.Compression;
+using AyCode.Core.Enums;
 using AyCode.Core.Extensions;
 using AyCode.Core.Helpers;
 using AyCode.Core.Interfaces;
+using AyCode.Core.Loggers;
+using AyCode.Core.Serializers;
+using AyCode.Core.Serializers.Binaries;
 using AyCode.Services.SignalRs;
+using Castle.Core.Logging;
 using System.Collections;
 using System.Collections.ObjectModel;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
-using AyCode.Core.Compression;
-using AyCode.Core.Serializers;
-using AyCode.Core.Serializers.Binaries;
 
 namespace AyCode.Services.Server.SignalRs
 {
@@ -218,8 +220,12 @@ namespace AyCode.Services.Server.SignalRs
         protected int FindIndexInnerListUnsafe(TId id) => InnerList.FindIndex(x => IdEquals(x.Id, id));
         protected TDataItem? FirstOrDefaultInnerListUnsafe(TId id) => InnerList.FirstOrDefault(x => IdEquals(x.Id, id));
 
-        public AcSignalRDataSource(AcSignalRClientBase signalRClient, SignalRCrudTags signalRCrudTags, object[]? contextIds = null)
+        private IAcLoggerBase? _logger;
+
+        public AcSignalRDataSource(AcSignalRClientBase signalRClient, SignalRCrudTags signalRCrudTags, IAcLoggerBase? logger, object[]? contextIds = null)
         {
+            _logger = logger;
+
             ContextIds = contextIds;
             SignalRCrudTags = signalRCrudTags;
             SignalRClient = signalRClient;
@@ -277,8 +283,7 @@ namespace AyCode.Services.Server.SignalRs
                 var rawBytes = await SignalRClient.GetAllAsync<byte[]>(SignalRCrudTags.GetAllMessageTag, GetContextParams())
                     ?? throw new NullReferenceException("LoadDataSource; null response");
 
-                await LoadDataSourceFromResponseData(rawBytes, SerializerType,
-                    false, false, clearChangeTracking);
+                await LoadDataSourceFromResponseData(rawBytes, SerializerType, false, false, clearChangeTracking);
             }
             finally
             {
@@ -301,11 +306,9 @@ namespace AyCode.Services.Server.SignalRs
                 {
                     try
                     {
-                        var rawBytes = await responseTask
-                            ?? throw new NullReferenceException("LoadDataSourceAsync; null response");
+                        var rawBytes = await responseTask ?? throw new NullReferenceException("LoadDataSourceAsync; null response");
 
-                        await LoadDataSourceFromResponseData(rawBytes, SerializerType,
-                            false, false, clearChangeTracking);
+                        await LoadDataSourceFromResponseData(rawBytes, SerializerType, false, false, clearChangeTracking);
                     }
                     finally
                     {
@@ -314,6 +317,39 @@ namespace AyCode.Services.Server.SignalRs
                 }).Unwrap();
         }
 
+        /// <summary>
+        /// Wraps a deserialize/populate call so a fault is logged with the concrete <typeparamref name="TDataItem"/>
+        /// type before it propagates. Placed directly around the deserialize call (inside any BeginUpdate/EndUpdate
+        /// scope, before EndUpdate runs) so the genuine root exception is captured even if EndUpdate's NotifyReset
+        /// throws a secondary exception that would otherwise overwrite it. Rethrows — callers' behaviour is unchanged.
+        /// </summary>
+        private void TryDeserialize(Action deserialize)
+        {
+            try
+            {
+                deserialize();
+            }
+            catch (Exception ex)
+            {
+                _logger?.Error($"Deserialize failed for {typeof(TDataItem).Name}", ex);
+                throw;
+            }
+        }
+
+        /// <inheritdoc cref="TryDeserialize(Action)"/>
+        private T TryDeserialize<T>(Func<T> deserialize)
+        {
+            try
+            {
+                return deserialize();
+            }
+            catch (Exception ex)
+            {
+                _logger?.Error($"Deserialize failed for {typeof(TDataItem).Name}", ex);
+                throw;
+            }
+        }
+
         /// <summary>
         /// Loads data source from response data.
         /// responseData is either a typed object (protocol deserialized) or byte[] (raw path).
@@ -336,7 +372,7 @@ namespace AyCode.Services.Server.SignalRs
                                 observable.BeginUpdate();
                                 try
                                 {
-                                    AcBinaryDeserializer.PopulateMerge(rawBytes, 0, rawBytes.Length, InnerList);
+                                    TryDeserialize(() => AcBinaryDeserializer.PopulateMerge(rawBytes, 0, rawBytes.Length, InnerList));
                                 }
                                 finally
                                 {
@@ -345,7 +381,7 @@ namespace AyCode.Services.Server.SignalRs
                             }
                             else
                             {
-                                AcBinaryDeserializer.Populate(rawBytes, 0, rawBytes.Length, InnerList);
+                                TryDeserialize(() => AcBinaryDeserializer.Populate(rawBytes, 0, rawBytes.Length, InnerList));
                             }
                         }
                         else
@@ -364,10 +400,8 @@ namespace AyCode.Services.Server.SignalRs
                     else
                     {
                         TIList? fromSource;
-                        if (serializerType == AcSerializerType.Binary)
-                            fromSource = AcBinaryDeserializer.Deserialize<TIList>(rawBytes, 0, rawBytes.Length);
-                        else
-                            fromSource = GzipHelper.DecompressToString(rawBytes).JsonTo<TIList>();
+                        if (serializerType == AcSerializerType.Binary) fromSource = TryDeserialize(() => AcBinaryDeserializer.Deserialize<TIList>(rawBytes, 0, rawBytes.Length));
+                        else fromSource = GzipHelper.DecompressToString(rawBytes).JsonTo<TIList>();
 
                         if (fromSource != null)
                         {
@@ -417,17 +451,23 @@ namespace AyCode.Services.Server.SignalRs
                         if (InnerList is IAcObservableCollection observable2)
                         {
                             observable2.BeginUpdate();
-                            try { AcBinaryDeserializer.PopulateMerge(reBytes, 0, reBytes.Length, InnerList); }
-                            finally { observable2.EndUpdate(); }
+                            try
+                            {
+                                TryDeserialize(() => AcBinaryDeserializer.PopulateMerge(reBytes, 0, reBytes.Length, InnerList));
+                            }
+                            finally
+                            {
+                                observable2.EndUpdate();
+                            }
                         }
                         else
                         {
-                            AcBinaryDeserializer.Populate(reBytes, 0, reBytes.Length, InnerList);
+                            TryDeserialize(() => AcBinaryDeserializer.Populate(reBytes, 0, reBytes.Length, InnerList));
                         }
                     }
                     else
                     {
-                        var fromSource = AcBinaryDeserializer.Deserialize<TIList>(reBytes, 0, reBytes.Length);
+                        var fromSource = TryDeserialize(() => AcBinaryDeserializer.Deserialize<TIList>(reBytes, 0, reBytes.Length));
                         if (fromSource != null)
                         {
                             ClearUnsafe(clearChangeTracking);