Using Fiddler with IIS7 Express

Question

This has nothing to do with IIS7 Express and everything to do with the fact that you’re using loopback traffic.

Ref: https://www.fiddlerbook.com/fiddler/help/hookup.asp#Q-LocalTraffic

Click Rules > Customize Rules.

Update your Rules file like so:

static function OnBeforeRequest(oSession:Fiddler.Session)
{
    if (oSession.HostnameIs("MYAPP")) { oSession.host = "localhost:portnumber"; }
}

Then, just visit http://myapp in your browser.

Or use the address http://localhost.fiddler/ and Fiddler will use the hostname localhost instead of converting to an IP address.