I might come after the war has ended but after a lot of investigation about my problem, I found something which might be interesting for you.
First of all: Ubuntu gnome 14.10 (clean install) What was my problem: Since today (1st of March : date is important here) GDM did not show up (black screen). >From my terminal, when loging in, I had the following 2 lines [ 7.287663] systemd-logind[1057]: Failed to start unit user@1000.service: Unknown unit: user@1000.service [ 7.287677] systemd-logind[1057]: Failed to start user service: Unknown unit: user@1000.service But I could do what I wanted and start looking for a workaround (like using lightdm) How I fixed my initial problem: I changed the language of the login screen for French (instead of German). Why: Using lightdm, I saw that the month of the today date was '(null)'. In German, March is März ... So I supposed any encoding compatibility problem occured, probably better managed with lightdm (null) than with gdm (hangs). And: It also removed the 2 error lines of systemd-logind Voilà, I hope it will help anyone -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1359439 Title: [ 7.287663] systemd-logind[1057]: Failed to start unit user@126.service: Unknown unit: user@126.service To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1359439/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs