I am unable to run any commands against my remote repository at Visual Studio Team Services (VSTS) because authentication fails.
I am able to do pulls, etc. through Visual Studio. But only through Visual Studio. Not through Git Bash, or any other tool like SourceTree.
You need to enable Alternate Authentication Credentials if you want to use other Git clients outside of Visual Studio...
To set up alternate creds in Visual Studio Team Services (VSTS), click on your name/icon on the top right -> Security -> Alternate Authentication Credentials
Edit: Add more details about this from VSTS (taken from the alternate credentials screen)...
ALTERNATE AUTHENTICATION CREDENTIALS
Some applications that work outside the browser (including Team Explorer Everywhere command line client and the git-tf utility) require basic authentication credentials. Other applications do not properly handle using an e-mail address for the user name during authentication.
To work with these applications, you need to enable alternate credentials, set a password, and optionally set a secondary user name not in the form of an e-mail address. Please note that alternate credentials cannot be used to sign in to the service from a web browser or outside of these applications.
Enable alternate authentication credentials and set secondary username
Create a personal access token for your Visual Studio Team Services account and copy the token
Open Git Bash and go to the folder that you cloned your repository to and enter the following command to make sure it stores the credentials and you don't need to enter it every time:
git config credential.helper store
git pull origin [your branch]
It asks for user name and password. Enter user name and token as password
On Windows, you can easily create a Personal Access Token using the Git Credential Manager. It's what Visual Studio Team Services now seems to recommend over the Alternate authentication credentials.
Just install that utility, and then the next time you git pull from Git Bash, it will prompt you for your Visual Studio Team Services access credentials. It will then create a Personal Access Token in your VSTS account, and add a couple of entries to your local Windows Credentials store.
Quote from the site:
It magically works when credentials are needed. For example, when pushing to Visual Studio Team Services, it automatically opens a window and initializes an oauth2 flow to get your token.
When using Atlassian SourceTree you need the basic credentials setup in Visual Studio Team Services (VSTS) like in the accepted answer.
Then in SourceTree go to menu Tools → Options → Authentication tab.
You need to set the non-email username that you set up as basic username credentials for the XXX.visualstudio.com host.
You will then be prompted for the password when accessing that VSTS Git repository.
