Hallo, yesterday i did an update of Wheezy Debian on my Samsung Netbook. Later I installed a bunch of packages on it. Over night i put it to hibernate and today morning I restarted my computer. The greeting after login was

"Oh no! Something has gone wrong.
A problem has occurred and the system can’t recover.
Please log out and try again.
[Log out]".

I dont know from where it comes.

My fix is quick and dirty, but it works (in Ubuntu too):
Log into terminal (Ctrl+ALT+F1) as root and add a new user.

# adduser userx
Now i answered what was asked. Ctrl+ALT+F7 brang me back to GUI and i logged in as userx.
Now I changed back to the Ctrl+ALT+F1 terminal and removed the /home/yourUserName/.config folder.
# rm -R /home/yourUserName/.config
The next step is to copy the .config folder from the new userx account to your normal user account folder.
# cp -R /home/userx/.config /home/yourUserName/
now press Ctrl+ALT+F7 to check, if it worked.

If it is good now, delete the new userx
# userdel -r userx
all your settings will be gone, but at least it is working again.