Using Mac OS 10.13.6 and Visual Studio for Mac Community v7.5.4 Trying to connect to my company’s TFS and access the files. I got stuck when it would not let me create a Workspace.
Yesterday I started working with a client who uses TFS with Git. My outlook.com account was added to the repo and Visual Studio 2017 connected fine once I was logged-in with this account.
I then wanted to pull the repo Visual Studio for Mac and discovered it's impossible using the Microsoft account outlook.com credentials - I just got unathorized messages.

I tried it in Git Bash too and had the same results. I think when Visual Studio connects on Windows it must stash a token which it then uses to authenticate itself and never uses the Microsoft account username and password.
Normally when I connect to GitHub or BitBucket using HTTPS, I only use a simple user name and password combiation so figured it must be possible, but not with the Microsoft email address. After a fair amount of googling, I discovered that there is the concept of Alternate authentication credentials
If you login to .visualstudio.com and click Manage security next to the repository:
You get the security menu where you can select Alternate authentication credentials:
In here, you can create your Alternate authentication credentials:

Once saved, the .visualstudio.com Git repository can be cloned either from Git or Visual Studio for Mac using these credentials.
Description
Martin Woodward dropped in to the studio to share the news that Git repos are now fully supported on Team Foundation Service and that Microsoft has released Visual Studio Tools for Git. You can now choose which source control system you prefer, either the centralized version control provided by Team Foundation Version Control (TFVC) or the distributed version control provided by Git - while maintaining the same integrated experience provided by the Visual Studio 2012, and getting all of the ALM benefits that come with TFS. Using Visual Studio and the Visual Studio Tools for Git extension, you can connect to any Git provider, whether it's Team Foundation Service or a third party.
In this short video, Martin takes us on a lightning tour of these new capabilities. If you would like to try this yourself head on over to http://tfs.visualstudio.com to get yourself an account with the Team Foundation Service, and/or download the Visual Studio Tools for Git.
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