Hi, I have the same pb. on my ubuntu xenial, here's what I get in the "lightdm.service" journal :
$ journalctl -au lightdm -S "2020-01-29 1:59" -- Logs begin at lun. 2020-01-27 11:14:43 CET, end at mer. 2020-01-29 02:01:47 CET. -- janv. 29 01:59:45 sebastien-B206 lightdm[11808]: Failed to write utmpx: Permission denied janv. 29 01:59:45 sebastien-B206 lightdm[11808]: Error writing to daemon: Bad file descriptor janv. 29 01:59:45 sebastien-B206 lightdm[11808]: Error writing to daemon: Bad file descriptor janv. 29 01:59:45 sebastien-B206 lightdm[11808]: Error writing to daemon: Bad file descriptor janv. 29 01:59:45 sebastien-B206 lightdm[11808]: Failed to write utmpx: Permission denied -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1782510 Title: lightdm automatically logs in after logout To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-keyring/+bug/1782510/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs