Using fiddler with Windows Authentication

Question

I am testing some proxy settings for our application but I need to test a proxy that requires Windows Authentication (or network credentials).

For testing, I assigne

Answer 1

You cannot easily do this with Fiddler; you'd need to calculate the credential challenge yourself and add the challenge in a response header after returning a HTTP/407 response with a Proxy-Authenticate: Negotiate header.

In contrast, BASIC authentication is easily supported with a single response header, which is how Fiddler's "Require Proxy Authentication" feature works.