I've just upgraded my system from 12.04 to 13.04. However, after typing in my login credentials the screen goes black for approx. 1 sec. and then the login screen reappears, asking me again for the password.
The password is the one I used also for the 12.04 version and the system seems to accept it. When I type in a wrong password on purpose the system notifies me in red letters that incorrect details were entered, which in turn is not the case when using the correct password. However, it then always keeps falling back to the login screen asking me again for the password.
Does anybody have an idea what could be wrong here?