As reported there is an issue with your Xorg config. LightDM doesn't generate this config.
** Changed in: lightdm (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1402149 Title: After update lightdm doesn't start Status in lightdm package in Ubuntu: Invalid Bug description: Updateted 14 Dec 2014 Kubuntu 14.10 64Bit After reboot there is no gui. From dmesg I see an error in ligthdm This is the error reported: [ 16.777309] init: lightdm main process (2534) terminated with status 1 [ 16.777317] init: lightdm main process ended, respawning [ 22.866231] init: lightdm main process (2642) terminated with status 1 [ 22.866239] init: lightdm main process ended, respawning [ 23.742651] systemd-logind[981]: Failed to start unit user@1000.service: Unknown unit: user@1000.service [ 23.742688] systemd-logind[981]: Failed to start user service: Unknown unit: user@1000.service [ 23.745586] systemd-logind[981]: New session c1 of user mirto. [ 28.947789] init: lightdm main process (2895) terminated with status 1 [ 28.947797] init: lightdm respawning too fast, stopped [ 28.951276] init: plymouth-ready (startup) main process (264) terminated with status 1 [ 33.762569] audit_printk_skb: 57 callbacks suppressed Trier another update this morning but nothing chenged ProblemType: Bug DistroRelease: Ubuntu 14.10 Package: lightdm 1.12.2-0ubuntu1 ProcVersionSignature: Ubuntu 3.16.0-28.38-generic 3.16.7-ckt1 Uname: Linux 3.16.0-28-generic x86_64 ApportVersion: 2.14.7-0ubuntu8 Architecture: amd64 Date: Sat Dec 13 07:50:08 2014 InstallationDate: Installed on 2014-11-24 (18 days ago) InstallationMedia: Kubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1) LightdmGreeterLog: QInotifyFileSystemWatcherEngine::addPaths: inotify_add_watch failed: File o directory non esistente QFileSystemWatcher: failed to add paths: /var/lib/lightdm/.config/ibus/bus Bus::open: Can not get ibus-daemon's address. IBusInputContext::createInputContext: no connection to ibus-daemon LightdmGreeterLogOld: QInotifyFileSystemWatcherEngine::addPaths: inotify_add_watch failed: File o directory non esistente QFileSystemWatcher: failed to add paths: /var/lib/lightdm/.config/ibus/bus Bus::open: Can not get ibus-daemon's address. IBusInputContext::createInputContext: no connection to ibus-daemon ProcEnviron: TERM=xterm PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=it_IT.UTF-8 SHELL=/bin/bash SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1402149/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp