Generating a gitlab ssh key from windows

ON windows if you have git for windows installed, run git-gui. Then click Help then click Show Ssh Key, then click Generate Key.

While you're at it, then copy to the clipboard, and then go to your Gitlab account page and add the SSH key to your Gitlab account's ssh settings.

The intention here is for %userprofile% to be an environment variable present in your system that contains your actual user's home directory. Either check why this environment variable isn't set on your system and fix it, or for a quick fix, replace %userprofile% in the above command with your actual user's home directory.