Changing username and password of fiddler proxy server

fiddler, passwords, proxy

Solution

The `X-AutoAuth` flag concerns what credentials Fiddler sends to an upstream server when automatically replying to an authentication challenge; it has no impact on what credentials are demanded of the user.

This question was original asked and answered here: https://groups.google.com/forum/#!topic/httpfiddler/pErxaOtMlyc

You can change the credentials expected by Fiddler by setting the preference `fiddler.proxy.creds` to the base64 encoded `username:password` string. The default value is `MToX` which is the base64 encoded version of the string `1:1`. You can compute the base64 value you need using the Tools > TextWizard feature in Fiddler.

To update the preference, click into the QuickExec box below Fiddler's Web Sessions list and type `prefs set fiddler.proxy.creds YOURBASE64StringHere` and hit Enter.

Problem

I'm using Fiddler to setup a proxy server, but when enabling "Require Proxy Authorization" under the rules menu the username/password is always 1. How do I change the username/password? I tried changing oSession["X-AutoAuth"] = "username:password"; but it doesn't change the proxy credentials required. Can't find anything in the documentation regarding this...

Original source