Question

I have a application that’s making calls against some WCF services I have hosted on my local IIS server. The IIS Server is running ASP.NET 4.0 classic and the services are developed using .NET 4.0. The client is running Windows Compact Framework 3.5 with auto generated service clients using the NetCFSvcUtil utility.

When I attempt to call one of the methods available to the client in my application, I receive the following exception:

ProtoccolException: The remote server returned an unexpected response: (501) Not Implemented.

Can anyone point me in the direction as to why I’m receiving this error? All the methods I’m calling have an implementation provided.

Stack Trace:

System.ServiceModel.ProtocolException was unhandled
  Message="The remote server returned an unexpected response: (501) Not Implemented."
  StackTrace:
       at System.ServiceModel.Channels.HttpChannelUtilities.ValidateRequestReplyResponse(HttpWebRequest request, HttpWebResponse response, HttpChannelFactory factory, WebException responseException)
       at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout)
       at System.ServiceModel.Channels.RequestChannel.Request(Message message, TimeSpan timeout)
       at System.ServiceModel.Channels.RequestChannel.Request(Message message)
       at ClientProject.Microsoft.Tools.ServiceModel.CFClientBase`1.getReply(Message msg)
       at ClientProject.Microsoft.Tools.ServiceModel.CFClientBase`1.Invoke[TREQUEST,TRESPONSE](CFInvokeInfo info, TestMethodRequest request)
       at ClientProject.TestService.MQClient.TestMethod(TestMethodRequest request)
       at ClientProject.TestService.MQClient.TestMethod(TestInfo testInfo)
       at ClientProject.Form.Button1_Click(Object sender, EventArgs e)
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnClick(EventArgs e)
       at System.Windows.Forms.ButtonBase.WnProc(WM wm, Int32 wParam, Int32 lParam)
       at System.Windows.Forms.Control._InternalWnProc(WM wm, Int32 wParam, Int32 lParam)
       at Microsoft.AGL.Forms.EVL.EnterMainLoop(IntPtr hwnMain)
       at System.Windows.Forms.Application.Run(Form fm)
       at ClientProject.Form.Main()
  InnerException: System.Net.WebException
       Message="The remote server returned an error: (501) Not Implemented."
       StackTrace:
            at System.Net.HttpWebRequest.finishGetResponse()
            at System.Net.HttpWebRequest.GetResponse()
            at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout)
            at System.ServiceModel.Channels.RequestChannel.Request(Message message, TimeSpan timeout)
            at System.ServiceModel.Channels.RequestChannel.Request(Message message)
            at ClientProject.Microsoft.Tools.ServiceModel.CFClientBase`1.getReply(Message msg)
            at ClientProject.Microsoft.Tools.ServiceModel.CFClientBase`1.Invoke[TREQUEST,TRESPONSE](CFInvokeInfo info, TestMethodRequest request)
            at ClientProject.TestService.MQClient.TestMethod(TestMethodRequest request)
            at ClientProject.TestService.MQClient.TestMethod(TestInfo testInfo)
            at ClientProject.Form.Button1_Click(Object sender, EventArgs e)
            at System.Windows.Forms.Control.OnClick(EventArgs e)
            at System.Windows.Forms.Button.OnClick(EventArgs e)
            at System.Windows.Forms.ButtonBase.WnProc(WM wm, Int32 wParam, Int32 lParam)
            at System.Windows.Forms.Control._InternalWnProc(WM wm, Int32 wParam, Int32 lParam)
            at Microsoft.AGL.Forms.EVL.EnterMainLoop(IntPtr hwnMain)
            at System.Windows.Forms.Application.Run(Form fm)
            at ClientProject.Form.Main()
       InnerException: 

Running the WCF Test Client on my service yields the following inner most exception:

Failed to invoke the service. Possible causes: The service is offline or inaccessible; the client-side configuration does not match the proxy; the existing proxy is invalid. Refer to the stack trace for more detail. You can try to recover by starting a new proxy, restoring to default configuration, or refreshing the service.


An error occurred while receiving the HTTP response to http://wv113.domain.local/Development/TestService.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.

Server stack trace: 
   at System.ServiceModel.Channels.HttpChannelUtilities.ProcessGetResponseWebException(WebException webException, HttpWebRequest request, HttpAbortReason abortReason)
   at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout)
   at System.ServiceModel.Channels.RequestChannel.Request(Message message, TimeSpan timeout)
   at System.ServiceModel.Dispatcher.RequestChannelBinder.Request(Message message, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)
   at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
   at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)

Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at IMQClient.TestMethod(TestInfo testInfo)
   at MQClient.TestMethod(TestInfo testInfo)

Inner Exception:
The underlying connection was closed: An unexpected error occurred on a receive.
   at System.Net.HttpWebRequest.GetResponse()
   at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout)

Inner Exception:
Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.
   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)

Inner Exception:
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)

Update: Everything was configured properly on my servers. The issues ended up actually being due to my local development machine missing the Message Queue component for one of the services. The other service was throwing exceptions because one of the configuration files given to me had the wrong settings within it. Lesson learned? Check the log files!

Answer 1

That means that the method you are trying to execute is not implemented on the WCF server side. Is this something you wrote?

Example of a method that would throw this exception:

public void UnimplementedMethod()
{
    throw new NotImplementedException();
}

This is usually the default markup of the method that is automatically generated by implementing an interface that class inherits from.

EDIT:

To make sure the method is implemented on the web service side goto Visual Studio Command Prompt and type wcftestclient. After the app is started, add service reference to the wcf you want to test and execute the method from there, to make sure it is functioning as expected.