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I have completed all suggested updates for 12.04 LTS after a long time of inactivity with my administrative account as the old laptop (Sony Vaio) was used by my wife only. After the update the Unity was gone (and a message like "Compiz was closed unexpectedly"). Trying every solution I found was not helpful. Eventually I upgraded to 14.04 LTS (by do-release-upgrade). When upgraded and rebooted, after logging in I get a pop-up "System problem detected". After a few seconds it comes back to login screen, and that's true for all users including guest user. I tried every suggested solution I found including changing lightdm to gdm to no avail. Again removed the Gnome desktop, problem persists. Would somebody please help to find a solution? I appreciate it.

marked as duplicate by WinEunuuchs2Unix, David Foerster, Eric Carvalho, Zanna, Ravan Nov 23 '16 at 2:38

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  • result of grep -H PATH ~/.profile is: PATH="$HOME/bin:$PATH". ~/bash_login does not exist. I am not sure whether it is OK? – Farzan Nov 20 '16 at 12:37

Set appropriate ownership to .Xauthority and .ICEauthority.

chown username:username .Xauthority
chown username:username .ICEauthority

Set permission for /tmp

sudo chmod a+wt /tmp

Restart lightdm

dpkg-reconfigure lightdm
sudo service lightdm restart

Reboot and login, this should fix your problem

If this doesn't fix your problem then remove incompatible graphics driver:

For Nvidia:

sudo nvidia-settings --uninstall 
sudo apt-get remove --purge nvidia*

For amd:

sudo apt-get purge fglrx* 
  • Thanks Rahul, dpkg-reconfigure lightdm does not execute, adding sudo did. The result was at the end unfortunately unsuccessful. Other ideas? – Farzan Nov 20 '16 at 12:14
  • post the output of "echo $PATH" – Rahul Nov 20 '16 at 12:22
  • /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games – Farzan Nov 20 '16 at 12:43
  • It seems that the graphics card update is causing some problem or unsupported driver is installed. I would suggest to you remove that driver. – Rahul Nov 20 '16 at 12:52
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    I know you're trying to help, but please stop posting this and the Broadcom answer everywhere you think it may be relevant. Most of your Broadcom answers do not apply, as the OP doesn't even have Broadcom, and your answer here is potentially dangerous. Instead of reposting answers, please flag as a duplicate, if you believe the same answer could apply. – TheWanderer Nov 21 '16 at 15:04

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