Fiddler not capturing traffic through app

[Chris]

Hi all,

Having a problem we can't figure out.  We've got Fiddler installed on our test machine, and when we create mockups that only test our API calls, it captures them all just fine.  However, when we run the app we're developing (on the same machine), which uses those same API calls, Fiddler captures nothing at all.  We're clueless.  Does anybody know why this would happen?

[Chris]

More information:

We tried adding

<configuration><system.net><defaultProxy><proxy bypassonlocal="false" usesystemdefault="true" /></defaultProxy></system.net></configuration>

to our app.config file, and it's had no effect.

We tried adding

<system.net><defaultProxy><proxy autoDetect="false" bypassonlocal="false" proxyaddress="http://127.0.0.1:8888" usesystemdefault="false" /></defaultProxy></system.net>

to our machine.config file, but it just blocked the port the app uses to communicate with our APIs.

 

It's a .Net 4 app running through a Windows Service (we do restart the service after starting Fiddler). 

If anybody has any ideas based on this, we'd appreciate it.

Thanks!

[Tsviatko Yovtchev]

Hello,

The changes to the machine.config should normally make a service use the proxy at  127.0.0.1:8888.Is there a firewall or some network traffic filtering/monitoring app on that machine? Is the machine part of a domain? The domain policies might interfere with proxy settings too.

Regards,
Tsviatko Yovtchev
Telerik

[Chris]

Thank you for the reply!  We actually just got it fixed this morning. Looks like it did have something to do with the domain policies.  Whatever it was, it's beyond my pay scale, but it's fixed now.