OS X - Can't start Git: /usr/bin/git Probably the path to Git executable is not valid

You should run sudo git --version on your command line. It will ask you to agree to the git xcode license agreement, once done everything will work as before.

When upgrading to MacOS Sierra I had to run: xcode-select --install

You should agree explicitly to user's licence agreement.

This is how you should do it:

  1. Open terminal
  2. run the following command: sudo xcodebuild -license
  3. agree to the terms.

That's it! :)