Login Loop - unable to run unity - not Xauthority ownership but may be related to display?
Solution 1:
Though you have given answer in your question, writing this for the record. Type ctrl + alt + F1 and login with your username at command prompt.
user@dell$ ls -l ~/.ICEauthority
-rw------- root root 3668 May 28 09:28 /home/user/.ICEauthority
user@dell$ sudo chmod 777 ~/.ICEauthority
password:
user@dell$ ls -l ~/.ICEauthority
-rwxrwxrwx root root 3668 May 28 09:28 /home/user/.ICEauthority
ctrl + alt + F7 and login worked.