This seems to happen every time I install a raring update or upgrade, but I haven't updated often enough to swear to this. I can tell you that I had this problem twice, which is exactly 2 times more than I should have.
Basically, I get the login greeter screen, type in my password, it goes away for a couple of seconds, and then returns to the greeter screen without any visible error message. This is a serious WTF moment. I was able to work around it (after a *lot* of scratching around and looking in /var/log/lightdm/ and elsewhere, which really didn't help much, and online searches, which did, eventually), as follows. In desperation, I created a new user using a console (Ctrl-Alt-F1) session and usermod (lucky for me, I know a bit of sysadmin stuff). It was able to log in with no problems, of course. After getting a clue that .Xauthority was the likely culprit, I simply copied the new user's .Xauthority file over the one in my home directory. This is not necessarily the best way to do it (probably deleting the file and running 'xauth generate :0 . trusted' is), but that's what got me over the hump. -- 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/1234400 Title: Cannot log in users if their Xauthority file is corrupt. Status in Light Display Manager: Fix Released Status in Light Display Manager 1.6 series: Fix Released Status in Light Display Manager 1.7 series: Fix Released Status in “lightdm” package in Ubuntu: Fix Released Status in “lightdm” source package in Raring: Fix Committed Status in “lightdm” source package in Saucy: Fix Released Bug description: Impact: If a users X authority file contains invalid data the user will not be able to log in with LightDM until the file is corrected or removed. The reason for the corruption has not been identified. To reproduce: 1. Stop lightdm $ sudo stop lightdm 2. Create an invalid X authority file in the home directory of a user, e.g. from a text VT: $ cp /etc/hostname ~/.Xauthority 3. Start lightdm $ sudo start lightdm 4. Log into the user account in the greeter Expected result: Logged into graphical session. Observed result: Returned to greeter, graphical session not shown. Regression potential: Change is small and was a regression in 1.6 due to accidental removal line resetting the error variable after reading the existing X authority file. Seems unlikely to cause any side-effects. To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1234400/+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
