git config global file - remove settings

You can edit the ~/.gitconfig file in your home folder. This is where all --global settings are saved.

Super late answer, but hopefully still helpful:

git config --global --unset-all user.name

Then you're free to:

git config --global --add user.name <whatever>

git config --global --unset-all user.name

Or you can just change the user name like this:

git config --global --replace-all user.name "New User Name"

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