The underlying connection was closed: An unexpected error occurred on receive - WCF

Question

I have a Winforms C# application on client side which is communicating with WCF Service to fetch data from DB. The DB is implemented on WCF using LINQ TO SQL Classes. The problem is that I've been successful in fetching the data to client app but at one place I get following exception:

System.Net.WebException: The underlying connection was closed: An unexpected
error occurred on a receive. ---> System.IO.IOException: Unable to read data
from the transport connection: An existing connection was forcibly closed by
the remote host. ---> System.Net.Sockets.SocketException: An existing
connection was forcibly closed by the remote host
  at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32
  size, SocketFlags socketFlags)
  at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset,
  Int32 size)
  --- End of inner exception stack trace ---
  at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset,
  Int32 size)
  at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size)
  at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean
  userRetrievedStream, Boolean probeRead)
  --- End of inner exception stack trace ---
  at System.Net.HttpWebRequest.GetResponse()
  at System.ServiceModel.Channels.HttpChannelFactory`1.HttpRequestChannel.HttpChannel
  Request.WaitForReply(TimeSpan timeout)   An error occurred while receiving
  the HTTP response to http://localhost:13121/AttendanceService.svc. This
  could be due to the service endpoint binding not using the HTTP protocol.
  This could also be due to an HTTP request context being aborted by the
  server (possibly due to the service shutting down). See server logs for
  more details.  System.Collections.ListDictionaryInternal

Client Code:

    private void UpdateDataGrid2()
    {
        using (AttendanceServiceClient client = new AttendanceServiceClient())
        {
            try
            {
                if (client.GetAllFaculty() != null)
                {
                    allFaculty = client.GetAllFaculty().ToList<FacultyTable>();
                }
            }
            catch (System.ServiceModel.CommunicationException ce)
            {
                MessageBox.Show(ce.InnerException + "   " + ce.Message + "  " + ce.Data);
            }
        }
        var bindingList = new BindingList<FacultyTable>(allFaculty);
        var source = new BindingSource(bindingList, null);
        dataGridView2.DataSource = source;
        dataGridView2.ReadOnly = true;
        dataGridView2.Columns[2].Visible = false;
    }

WCF Code:

    public List<FacultyTable> GetAllFaculty()
    {
        using (AttendanceDataContext db = new AttendanceDataContext())
        {
            var exists = from x in db.FacultyTables
                         select x;

                return exists.ToList<FacultyTable>();
        }
    }

The trace from ".svclog" file generated from WCF says:

<E2ETraceEvent xmlns="http://schemas.microsoft.com/2004/06/E2ETraceEvent"><System xmlns="http://schemas.microsoft.com/2004/06/windows/eventlog/system"><EventID>524340</EventID><Type>3</Type><SubType Name="Error">0</SubType><Level>2</Level><TimeCreated SystemTime="2015-03-19T14:12:20.6344448Z" /><Source Name="System.ServiceModel" /><Correlation ActivityID="{639f5dfd-953b-4437-a479-72c96a96b955}" /><Execution ProcessName="iisexpress" ProcessID="5180" ThreadID="12" /><Channel /><Computer>AHMED-PC</Computer></System><ApplicationData><TraceData><DataItem><TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Error"><TraceIdentifier>http://msdn.microsoft.com/en-US/library/System.ServiceModel.ServiceOperationExceptionOnReply.aspx</TraceIdentifier><Description>Replying to an operation threw a exception.</Description><AppDomain>/LM/W3SVC/2029513164/ROOT-1-130712479142359422</AppDomain><Source>System.ServiceModel.Dispatcher.ImmutableDispatchRuntime/1177678</Source><Exception><ExceptionType>System.ObjectDisposedException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType><Message>Cannot access a disposed object.
Object name: 'DataContext accessed after Dispose.'.</Message><StackTrace>   at System.Data.Linq.DataContext.GetTable(Type type)
   at System.Data.Linq.CommonDataServices.GetDataMemberQuery(MetaDataMember member, Expression[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.ExecuteKeyQuery(Object[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.Execute(Object instance)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.DeferredSource.GetEnumerator()
   at System.Data.Linq.EntitySet`1.Load()
   at System.Data.Linq.EntitySet`1.get_Count()
   at WriteArrayOfSectionTableToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract )
   at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle)
   at WriteFacultyTableToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , ClassDataContract )
   at System.Runtime.Serialization.ClassDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle)
   at WriteArrayOfFacultyTableToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract )
   at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.DataContractSerializer.InternalWriteObjectContent(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
   at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
   at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
   at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph)
   at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameterPart(XmlDictionaryWriter writer, PartInfo part, Object graph)
   at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameter(XmlDictionaryWriter writer, PartInfo part, Object graph)
   at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeBody(XmlDictionaryWriter writer, MessageVersion version, String action, MessageDescription messageDescription, Object returnValue, Object[] parameters, Boolean isRequest)
   at System.ServiceModel.Dispatcher.OperationFormatter.SerializeBodyContents(XmlDictionaryWriter writer, MessageVersion version, Object[] parameters, Object returnValue, Boolean isRequest)
   at System.ServiceModel.Dispatcher.OperationFormatter.OperationFormatterMessage.OperationFormatterBodyWriter.OnWriteBodyContents(XmlDictionaryWriter writer)
   at System.ServiceModel.Channels.BodyWriterMessage.OnWriteBodyContents(XmlDictionaryWriter writer)
   at System.ServiceModel.Channels.Message.OnWriteMessage(XmlDictionaryWriter writer)
   at System.ServiceModel.Channels.BufferedMessageWriter.WriteMessage(Message message, BufferManager bufferManager, Int32 initialOffset, Int32 maxSizeQuota)
   at System.ServiceModel.Channels.TextMessageEncoderFactory.TextMessageEncoder.WriteMessage(Message message, Int32 maxMessageSize, BufferManager bufferManager, Int32 messageOffset)
   at System.ServiceModel.Channels.HttpOutput.SerializeBufferedMessage(Message message, Boolean shouldRecycleBuffer)
   at System.ServiceModel.Channels.HttpOutput.Send(TimeSpan timeout)
   at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReplyCore(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReply(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.HttpRequestContext.OnReply(Message message, TimeSpan timeout)
   at System.ServiceModel.Activation.HostedHttpContext.OnReply(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.RequestContextBase.Reply(Message message, TimeSpan timeout)
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.Reply(MessageRpc&amp;amp; rpc)</StackTrace><ExceptionString>System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'DataContext accessed after Dispose.'.
   at System.Data.Linq.DataContext.GetTable(Type type)
   at System.Data.Linq.CommonDataServices.GetDataMemberQuery(MetaDataMember member, Expression[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.ExecuteKeyQuery(Object[] keyValues)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.Execute(Object instance)
   at System.Data.Linq.CommonDataServices.DeferredSourceFactory`1.DeferredSource.GetEnumerator()
   at System.Data.Linq.EntitySet`1.Load()
   at System.Data.Linq.EntitySet`1.get_Count()
   at WriteArrayOfSectionTableToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract )
   at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle)
   at WriteFacultyTableToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , ClassDataContract )
   at System.Runtime.Serialization.ClassDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.InternalSerialize(XmlWriterDelegator xmlWriter, Object obj, Boolean isDeclaredType, Boolean writeXsiType, Int32 declaredTypeID, RuntimeTypeHandle declaredTypeHandle)
   at WriteArrayOfFacultyTableToXml(XmlWriterDelegator , Object , XmlObjectSerializerWriteContext , CollectionDataContract )
   at System.Runtime.Serialization.CollectionDataContract.WriteXmlValue(XmlWriterDelegator xmlWriter, Object obj, XmlObjectSerializerWriteContext context)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.WriteDataContractValue(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithoutXsiType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle declaredTypeHandle)
   at System.Runtime.Serialization.DataContractSerializer.InternalWriteObjectContent(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
   at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
   at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph, DataContractResolver dataContractResolver)
   at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph)
   at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameterPart(XmlDictionaryWriter writer, PartInfo part, Object graph)
   at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameter(XmlDictionaryWriter writer, PartInfo part, Object graph)
   at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeBody(XmlDictionaryWriter writer, MessageVersion version, String action, MessageDescription messageDescription, Object returnValue, Object[] parameters, Boolean isRequest)
   at System.ServiceModel.Dispatcher.OperationFormatter.SerializeBodyContents(XmlDictionaryWriter writer, MessageVersion version, Object[] parameters, Object returnValue, Boolean isRequest)
   at System.ServiceModel.Dispatcher.OperationFormatter.OperationFormatterMessage.OperationFormatterBodyWriter.OnWriteBodyContents(XmlDictionaryWriter writer)
   at System.ServiceModel.Channels.BodyWriterMessage.OnWriteBodyContents(XmlDictionaryWriter writer)
   at System.ServiceModel.Channels.Message.OnWriteMessage(XmlDictionaryWriter writer)
   at System.ServiceModel.Channels.BufferedMessageWriter.WriteMessage(Message message, BufferManager bufferManager, Int32 initialOffset, Int32 maxSizeQuota)
   at System.ServiceModel.Channels.TextMessageEncoderFactory.TextMessageEncoder.WriteMessage(Message message, Int32 maxMessageSize, BufferManager bufferManager, Int32 messageOffset)
   at System.ServiceModel.Channels.HttpOutput.SerializeBufferedMessage(Message message, Boolean shouldRecycleBuffer)
   at System.ServiceModel.Channels.HttpOutput.Send(TimeSpan timeout)
   at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReplyCore(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.HttpPipeline.EmptyHttpPipeline.SendReply(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.HttpRequestContext.OnReply(Message message, TimeSpan timeout)
   at System.ServiceModel.Activation.HostedHttpContext.OnReply(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.RequestContextBase.Reply(Message message, TimeSpan timeout)
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.Reply(MessageRpc&amp;amp; rpc)</ExceptionString></Exception></TraceRecord></DataItem></TraceData></ApplicationData></E2ETraceEvent>

Add WCF tracing and it'll probably point you straight to the error. See this post for details : http://stackoverflow.com/questions/29085566/wcf-service-failed-to-invoke-service/29086326#29086326 — mcr, Mar 18 '15 at 16:05
Possibly unrelated, but don't [wrap your client in a `using` block](http://stackoverflow.com/questions/573872/what-is-the-best-workaround-for-the-wcf-client-using-block-issue) - "The core ClientBase class throws on Dispose() under a range of fault conditions - with the side effect that you can very easily end up accidentally losing your original exception to a using block" — stuartd, Mar 18 '15 at 16:06
@mcrimes: I followed that post and the ".scvlog" file generated is giving some exception which says - "Replying to an operation threw a exception.", "RequestContext aborted." and "Failed to send response message over HTTP." — mohdahmed108, Mar 19 '15 at 14:20
@stuartd: I've also removed the 'using' block, but it made no difference. — mohdahmed108, Mar 19 '15 at 14:23
@stuartd: Thanks man. The 'using' block was the problem, I was removing it from client code and it wasn't working. But now I removed it from WCF code and it solved the problem. — mohdahmed108, Mar 19 '15 at 14:33

The underlying connection was closed: An unexpected error occurred on receive - WCF

0 Answers0