Manual:InvalidateUserSessions.php

Details
invalidateUserSessions.php maintenance script invalidates the sessions of certain users on the wiki. After the session invalidate, the users will be logged out from the browser/app.

If you want to invalidate all sessions, use $wgAuthenticationTokenVersion instead.

Options
Although both options are optional. But either --user or --file is required to run the script.

Common errors
It comes when you try to use both options at once. You always have to use either --user or --file at once.
 * Cannot use both --user and --file

It comes when the file does not exist or the user running the script does not have permission to read the file.
 * Could not open $filename

In case file does exist, check file permission. If you are root user then you can run script with sudo.