Getting Git to work with public key

[kinook]

That output is coming from git, not Visual Build. Check the Log the command-line option on the Advanced tab of the action, rebuild the step, and compare the git command-line call that was used with the working git command.

[ub3rst4r]

I figured out that the problem was using Github for Windows instead of msysgit.

For future reference, I downloaded and downloaded msysgit (from https://msysgit.github.io/). When you get to the step that says "Adjusting your PATH environment", make sure that "Run Git from the Windows command prompt" is selected (if this isn't selected, Visual Build might fail because git could not be found). Then at the step that says "Choosing the SSH Executable", I selected "Use Plink". You will have to make sure Pageant is setup to work with your GitHub account (instructions for that can be found here) and Pageant will need to be running in the background in order for Git to properly authenticate with GitHub.com.