Getting ".. unable to access 'tfs-URL': the requested URL returned error:407

When trying to fetch/pull or push I get the error 407.

• I've tried checking the devenv.exe.config-file, which is correct
• I've checked and reset my tfs-credentials, which didn't change anything
• I do not want my credentials to be shown in the gitconfig-file, so that is not an option
• I can logon to tfs via the link provided in the error.
• I've done a gpupdate -force, which didn't help either.

I do though suspect, that the error occurred when trying to play with Fiddler, since after that I haven't had any option to fetch, pull or push to the repo - has anyone else tried that?

Or is there somehow a way that I can debug the error locally? I've tried checking the other answers/questions in SO, but they either didn't cut my problem or was not related.

For some reason - as I said, I dont want credentials to be shown in gitconfig - when checked, it showed that some very old credentials was saved in there. Why, I don't know, but they were, and deleting them manually by opening the gitignore-file and removing the line, solved the problem.

The weird thing is that it worked last week, and the old credentials that was shown in gitignore are some, that I haven't used for months (they've been changed some times since), so that part I don't understand, but hey - it works now..