The problem seems be unity-greeter. http://ubuntuforums.org/showthread.php?t=1871466
I had the same problem, and it was due to unity-greeter segfaulting (visible in /var/log/kern.log). I purged unity-greeter and installed lightdm-gtk-greeter, and modified /etc/lightdm/lightdm.conf to use "greeter-session=lightdm-gtk-greeter". It works. ** Tags added: unity-greeter -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/921995 Title: lightdm doesn't start: Maximum number of clients reached To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unity-greeter/+bug/921995/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
