An error occurred while trying to make a request to URI ‘http://localhost/T2WS/AdminServices.asmx’. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent. Please see the inner exception for more details.

The error message was self-explanatory but it didnt’ solve the problem. I had my cross domain file setup appropriately and yet I was still receiving the error. As seen below the stack trace didn’t offer much help either:

System.ServiceModel.CommunicationException was unhandled by user code
Message=”An error occurred while trying to make a request to URI ‘http://localhost/T2WS/AdminServices.asmx’. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent. Please see the inner exception for more details.”
StackTrace:
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 T2SL.T2AdminService.AdminServicesSoapClient.AdminServicesSoapClientChannel.EndgetAccountList(IAsyncResult result)
at T2SL.T2AdminService.AdminServicesSoapClient.T2SL.T2AdminService.AdminServicesSoap.EndgetAccountList(IAsyncResult result)
at T2SL.T2AdminService.AdminServicesSoapClient.EndgetAccountList(IAsyncResult result)
at T2SL.T2AdminService.AdminServicesSoapClient.OnEndgetAccountList(IAsyncResult result)
at System.ServiceModel.ClientBase`1.OnAsyncCallCompleted(IAsyncResult result)
InnerException: System.Security.SecurityException
Message=”"
StackTrace:
at System.Net.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)
at System.Net.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelAsyncRequest.CompleteGetResponse(IAsyncResult result)
InnerException: System.Security.SecurityException
Message=”Security error.”
StackTrace:
at System.Net.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClass5.<EndGetResponse>b__4(Object sendState)
at System.Net.AsyncHelper.<>c__DisplayClass2.<BeginOnUI>b__0(Object sendState)
InnerException:

Still no luck, i spent some time fiddling with the clientaccesspolicy.xml file but it didn’t seem to be the problem. After a bit of digging and avoiding the obvious, it finally hit me right between the eyes. I had setup the Silverlight project to be the startup and it was running the file locally, instead of running it through the web project I had setup to wrap Silverlight with.

Once I changed the startup project to the Web project and the file to the Silverlight testpage everything worked just fine and dandy except that the Silverlight project wasn’t updating. Looking through the Silverlight project properties I was able to point the build for the Silverlight “executable” to the Web project’s ClientBin directory and everything fell into place.

I just mention this hear because I’m sure I’ll forget how I solved this problem the next time I run into it.