我正在使用 Nginx + FastCGI-Mono-Server 来托管一个小型的 asp.net Web 服务。使用 FastCGI-Mono-Server2（即 .Net 2.0 版本）运行良好。我现在需要将 asp.net 应用程序升级到 .net 4.0。这意味着我需要升级到 FastCGI-Mono-Server4。我把所有正确的文件都放好了。有用！但是，它总是因一个神秘的错误而崩溃。
这是错误：
异常：System.Runtime.FatalException
消息：对象引用未设置为对象的实例。
StackTrace：在 System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage4(MessageRpc& rpc) 在 System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage31(MessageRpc& rpc) 在 System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage3(MessageRpc& rpc) 在 System.ServiceModel.Dispatcher .ImmutableDispatchRuntime.ProcessMessage2(MessageRpc& rpc) 在 System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage11(MessageRpc& rpc) 在 System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage1(MessageRpc& rpc) 在 System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)在 System.ServiceModel.Dispatcher.ChannelHandler.DispatchAndReleasePump（RequestContext 请求，布尔型 cleanThread，OperationContext currentOperationContext) 在 System.ServiceModel.Dispatcher.ChannelHandler.OnAsyncReceiveComplete(IAsyncResult result) 在 System.ServiceModel.Dispatcher.ChannelHandler.AsyncMessagePump(IAsyncResult result) 在 System.ServiceModel.Dispatcher.ChannelHandler.HandleRequest(RequestContext request, OperationContext currentOperationContext) 在 System .Runtime.Fx.AsyncThunk.UnhandledExceptionFrame(IAsyncResult 结果) 在 System.Runtime.AsyncResult.Complete(Boolean completedSynchronously) 在 System.ServiceModel.Channels.FramingDuplexSessionChannel.TryReceiveAsyncResult.OnReceive(IAsyncResult 结果) 在 System.Runtime.Fx.AsyncThunk.UnhandledExceptionFrame （IAsyncResult 结果）在 System.ServiceModel.Channels.SynchronizedMessageSource 的 System.Runtime.AsyncResult.Complete（Boolean completedSynchronously）。System.ServiceModel.Channels.SocketConnection.FinishRead() 的 System.ServiceModel.Channels.SessionConnectionReader.OnAsyncReadComplete(Object state) 的 System.ServiceModel.Channels.SocketConnection.AsyncReadCallback 的 ReceiveAsyncResult.OnReceiveComplete(Object state) (Boolean haveResult, Int32 错误, Int32 bytesRead）在 System.ServiceModel.Channels.OverlappedContext.CompleteCallback（UInt32 错误，UInt32 numBytes，NativeOverlapped* nativeOverlapped）在 System.Runtime.Fx.IOCompletionThunk.UnhandledExceptionFrame（UInt32 错误，UInt32 bytesRead，NativeOverlapped* nativeOverlapped）在 System.Threading。 _IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)OnAsyncReadComplete(Object state) at System.ServiceModel.Channels.SocketConnection.FinishRead() at System.ServiceModel.Channels.SocketConnection.AsyncReadCallback(Boolean haveResult, Int32 error, Int32 bytesRead) at System.ServiceModel.Channels.OverlappedContext.CompleteCallback(UInt32 error , UInt32 numBytes, NativeOverlapped* nativeOverlapped) 在 System.Runtime.Fx.IOCompletionThunk.UnhandledExceptionFrame(UInt32 错误, UInt32 bytesRead, NativeOverlapped* nativeOverlapped) 在 System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)OnAsyncReadComplete(Object state) at System.ServiceModel.Channels.SocketConnection.FinishRead() at System.ServiceModel.Channels.SocketConnection.AsyncReadCallback(Boolean haveResult, Int32 error, Int32 bytesRead) at System.ServiceModel.Channels.OverlappedContext.CompleteCallback(UInt32 error , UInt32 numBytes, NativeOverlapped* nativeOverlapped) 在 System.Runtime.Fx.IOCompletionThunk.UnhandledExceptionFrame(UInt32 错误, UInt32 bytesRead, NativeOverlapped* nativeOverlapped) 在 System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)OverlappedContext.CompleteCallback(UInt32 error, UInt32 numBytes, NativeOverlapped* nativeOverlapped) at System.Runtime.Fx.IOCompletionThunk.UnhandledExceptionFrame(UInt32 error, UInt32 bytesRead, NativeOverlapped* nativeOverlapped) at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes,本机重叠* pOVERLAP)OverlappedContext.CompleteCallback(UInt32 error, UInt32 numBytes, NativeOverlapped* nativeOverlapped) at System.Runtime.Fx.IOCompletionThunk.UnhandledExceptionFrame(UInt32 error, UInt32 bytesRead, NativeOverlapped* nativeOverlapped) at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes,本机重叠* pOVERLAP)
内部异常：System.NullReferenceException
消息：对象引用未设置为对象的实例。
StackTrace：在 System.Web.HttpApplication.OnThreadEnterPrivate(Boolean setImpersonationContext) 在 System.Web.HttpApplication.ThreadContext.Enter(Boolean setImpersonationContext) 在 System.Web.AspNetSynchronizationContext.CallCallbackPossiblyUnderLock(SendOrPostCallback 回调，对象状态) 在 System.Web.AspNetSynchronizationContext。 CallCallback(SendOrPostCallback callback, Object state) at System.Web.AspNetSynchronizationContext.Post(SendOrPostCallback callback, Object state) at System.ServiceModel.Dispatcher.ThreadBehavior.BindCore(MessageRpc& rpc, Boolean startOperation) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage4 (MessageRpc&rpc)
我在项目中有一个 IHttpAsyncHandler 。我想知道它是否与此有关。当我搜索我的错误时，我发现有人（例如：更新到 .net 4.0 后的 wcf 回调异常）推荐此属性：
[回调行为（UseSynchronizationContext=false）]
据我所知，这是 WCF 的事情，与我的 asp.net Web 服务器无关。任何想法，将不胜感激！
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