It’s difficult to troubleshoot Silverlight applications built with WCF RIA services on a production environment because:
1) RIA Domain services is a virtual file and you will not find it in the directory structure.
2) Any exception thrown by the domain service will NOT be shown on the Silverlight client. It will only show up as a 404 Not found error. Without the real error, it’s very difficult to troubleshoot the problem.
In this post, I’m going to show you how to get the real error returned by the RIA domain service.
In this example, I am using the HR Application sample downloaded from Microsoft. With the Silverlight application, all I am seeing is the Not Found error which is not very helpful.
To get the real error returned by the domain service, you will need to install the HTTP Debugging Proxy tool, Fiddler.
Once you have Fiddler installed, you can fire up a Fiddler session and start capturing the HTTP requests.
In the Fiddler trace below, you can see that the request made to the domain service, /riarc2test/ClientBin/HRApp-Web-AuthenticationService.svc/binary/GetUser, returned a 500 error. In the web view on the right hand pane, Fiddler will display the real error returned by the domain service.