Visual Studio 2017 - Git failed with a fatal error

After I changed the generic credentials from Control Panel → User Accounts → Credential Manager for Git, it worked for me.

I'm going to add a solution here that the previous answers have not already mentioned, but this is what fixed it for me.

1. Navigate to C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\CommonExtensions\Microsoft\TeamFoundation\Team Explorer\ and delete the Git folder.

2. Make sure that there is no version of Git installed on your system, remove it by going to Control Panel → Program and Features (TortoiseGit does not need to be removed from my experience, just native git installations).

3. Open up the Visual Studio 2017 installer and untick "Git For Windows" in installation options.

4. Head over to the Git website and install the latest version of Git for Windows.

5. Go back into the Visual Studio installer and tick "Git for Windows" again. It will not download a new version even though it may look like it is. After that is done, your Git should be fine with VSTS and TF Explorer.

I had a different problem. My computer contained older OpenSSL DLL files in system32 and syswow64 so to fix my problem, I had to copy libeay32.dll and ssleay32.dll from one folder to another folder within the Git folders of Visual Studio 2017.

FROM: C:\Program Files (x86)\Microsoft Visual Studio\2017\vs_edition\Common7\IDE\CommonExtensions\Microsoft\TeamFoundation\Team Explorer\Git\mingw32\bin\

TO: C:\Program Files (x86)\Microsoft Visual Studio\2017\vs_edition\Common7\IDE\CommonExtensions\Microsoft\TeamFoundation\Team Explorer\Git\mingw32\libexec\git-core

Ref.: Git - Can't clone remote repository