Unable to sign in. How to debug?

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http://askubuntu.com – I had to reboot system with reset button. After reboot I can't sign in. When I enter my password It seems like X-server just restarts. I can sing in as guest and also I can sign in in text TTY. Here is first 150 lines of my lightdm.log: [+0.04s] DEBUG: Logging to /var/log/lightdm/lightdm.log [+0.04s] DEBUG: Starting Light Display Manager 1.2.1, UID=0 PID=1070 [+0.04s] DEBUG: Loaded configuration from /etc/lightdm/lightdm.conf [+0.04s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager [+0.04s] DEBUG: Registered seat module xlocal [+0.04s] DEBUG: Registered seat module xremote [+0.04s] DE (HowTos)