Can I capture traffic with Fiddler OOB Silverlight 4 app?

Question

I've got a Silverlight 4 OOB elevated trust app. I am trying to debug my WCF calls but I can't capture traffic in Fiddler (latest version).

I am running in debug mode with the service calls and app on same machine. I have tried without the debugger attached and without Visual Studio. I checked the filters on Fiddler (none), made sure it is capture traffic (web browser traffic is captured) and all processes.

My app is running with elevated trust but is not digitally signed.

When running in browser I changed to localhost. to get Fiddler to work but I can't do that in OOB.

I am pretty sure I have used Fiddler before with OOB - is it possible, and if so, any ideas? Thanks!

Answer 1

The best option here is to change your WCF endpoints on the Silverlight side. Instead of pointing to http://localhost, set it to http://ipv4.fiddler. This will force the OOB application to push traffic through fiddler.

So if your WCF service URL is -> http://localhost:9000/MyService.svc, the fiddler url would be http://ipv4.fiddler:9000/MyService.svc

In case you're interested, there is also http://ipv6.fiddler. :)