My ubuntu has just crashed. Now that I restarted it, it does nothing when I enter my password. The screen just gets refreshed leaving the password space empty again. However, if I try to enter a wrong password, it recognize that it is an invalid password. There is also a weird white box around the user names and password in the ubuntu log in page.
A worth mentioning point is that while I was using Ctrl+Alt+Del to restart the computer the window that asks whether I want to restart or shut down the computer was not able to show the characters, there were blank squares instead of each character.
I have tried to set a new password for my user by logging into recovery shell, but it did not work! I also created a new user but couldn't log in to that neither:(
Any suggestion how I can fix it?