So far I've been successfully using fiddler to sniff web service traffic from both test fixtures, console apps and web projects.

Today I noticed I am not able anymore to sniff that kind of traffic if I am running my web application (it's a ASP.NET website, hosted locally on IIS). I see all the local traffic but the web service traffic is just gone (the service is being hit as I do see the response debugging into the code).

I am still able to successfully sniff soap requests and responses from test fixtures or console apps in the same solution (exact same environment).

If it was a windows (I am on Win7) security update or the likes it would never work I guess (unless it affects only traffic routed through IIS).

What should I be looking for that could cause the emergence this behavior?

Any pointers appreciated!