I upgraded my Ubuntu Desktop to version 4.4.0-131-generic and start having this problem.
Step to reproduce error;
- login your user then lock screen.
- login another user then lockout. (Noticed that if I lock 2nd account the switch account option isn’t respond when I select in the top menu on login screen.)
- Login your user and lock screen again. You’ll see
Authentication Failureerror in red in the login box and you must select
Switch to greeterto login again.
I read this bug.
Is there any idea here? Reinstall OS isn’t the best choice cause I have more than 300 computers to upgrade.