Silverlight + Wcf：CommunicationException：远程服务器返回错误：Not Found

Question

我真的很奇怪。我加载了我的silverlight应用程序，如果我打电话给服务，让我们说接下来30秒（或者说立即说）一切正常。但是，如果我在加载应用程序后2分钟调用该服务，我将获得

{System.ServiceModel.CommunicationException: The remote server returned an error: NotFound. ---> System.Net.WebException: The remote server returned an error: NotFound. ---> System.Net.WebException: The remote server returned an error: NotFound.
   at System.Net.Browser.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
   at System.Net.Browser.BrowserHttpWebRequest.<>c__DisplayClassa.<EndGetResponse>b__9(Object sendState)
   at System.Net.Browser.AsyncHelper.<>c__DisplayClass4.<BeginOnUI>b__0(Object sendState)
   --- End of inner exception stack trace ---
   at System.Net.Browser.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)
   at System.Net.Browser.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
   at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelAsyncRequest.CompleteGetResponse(IAsyncResult result)
   --- End of inner exception stack trace ---
   at System.ServiceModel.AsyncResult.End[TAsyncResult](IAsyncResult result)
   at System.ServiceModel.Channels.ServiceChannel.SendAsyncResult.End(SendAsyncResult result)
   at System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result)
   at System.ServiceModel.ClientBase`1.ChannelBase`1.EndInvoke(String methodName, Object[] args, IAsyncResult result)
   at EnrollPortal.UI.SL.EnrollApp.FitC.FitCWatchlistMatcherClient.FitCWatchlistMatcherClientChannel.EndAssessBiometricQuality(IAsyncResult result)
   at EnrollPortal.UI.SL.EnrollApp.FitC.FitCWatchlistMatcherClient.EnrollPortal.UI.SL.EnrollApp.FitC.IFitCWatchlistMatcher.EndAssessBiometricQuality(IAsyncResult result)
   at EnrollPortal.UI.SL.EnrollApp.FitC.FitCWatchlistMatcherClient.OnEndAssessBiometricQuality(IAsyncResult result)
   at System.ServiceModel.ClientBase`1.OnAsyncCallCompleted(IAsyncResult result)}

如果我浏览服务本身就可以了。

感谢提示！