We are working on Xcode Project connected to our local TFS 2013 (Update 3) Server via TFS Provided Git Repository.
When we use older version of Xcode, we are successfully able to check-in the files and perform all other Git operations. We are also able to perform all Git Operations via command line Git.
The trouble is when we use latest version of Xcode - Version 7.1 (7B91b). On entering valid credentials, we are getting error saying
Authentication failed because the user name or password was incorrect.
The same credentials / configuration work on older version of Xcode and Git Command Line Options.
To add more to the surprises, we are able to connect to github.com successfully.
We are able to reproduce issue on other systems too. Please provide us the best way to resolve this error.
For us it turned out to be because Xcode 7 does not support Windows Authentication. The solution described here solved it for us:
"This happens because XCode 7 doesn't support Windows Authentication. I don't know why. It seems to be a common problem amongst users because there are many posts about it in google.
To make it all work you should enable Basic Authentication in your IIS TFS website on "tfs" virtual folder.
Be careful though because basic authentication sends your credentials over network as plain text. You definitely must use SSL in this case."
(source)