I can confirm this bug, but have tried several stored kernels going back to 3.2.0-29-generic and the problem doesn't seem to be related to the kernel version. I note that a new version of lightdm came out several days ago and perhaps the problem is there.
As a fairly acceptable workaround for this problem, enable /etc/rc.local and add the following lines to it: /sbin/start lightdm exit $? -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1188131 Title: lightdm does not start on boot Status in “lightdm” package in Ubuntu: Confirmed Bug description: Lightdm fails to start on boot up, resulting in a blank screen. Lightdm can be started manually from tty1, for example, after the machine has been booted up. If the default browser is set to gdm, then gdm starts up on boot. This problem first arose immediately after upgrade to 3.2.0-45-generic (from 3.2.0-44) in Ubuntu 12.04.2 LTS I have tried, to no avail, 1. Moving etc/X11/xorg.conf to a backup 2. uninstalling unity-greeter, lightdm, lightdm-gobject-1-0 3. deleting /etc/lightdm and /var/lib/lightdm 4. rebooting and reinstalling unity-greeter, lightdm, lightdm-gobject-1-0 5. Adding the line "sleep 2" immediately before "exec lightdm" in /etc/init/lightdm.conf 6. Checking that /etc/X11/default-display-manager says "/usr/sbin/lightdm" After reinstalling all the above it was necessary to change ownership of .Xauthority from root to my userid, to allow lightdm to accept a password. After this lightdm still works but still does not start up on boot. ProblemType: Bug DistroRelease: Ubuntu 12.04 Package: lightdm 1.2.3-0ubuntu2.1 ProcVersionSignature: Ubuntu 3.2.0-45.70-generic-pae 3.2.44 Uname: Linux 3.2.0-45-generic-pae i686 ApportVersion: 2.0.1-0ubuntu17.2 Architecture: i386 Date: Thu Jun 6 11:35:30 2013 MarkForUpload: True ProcEnviron: LANGUAGE=en_GB:en TERM=xterm PATH=(custom, no user) LANG=en_GB.UTF-8 SHELL=/bin/bash SourcePackage: lightdm UpgradeStatus: Upgraded to precise on 2012-04-29 (403 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1188131/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
