I was running Kali Linux 2.0 Sansa. I did the Kali Linux
apt-get update
&& apt-get upgrade
To upgrade to Kali 2.0 rolling edition now I cannot log in The user name and password still work because if I do Ctrl+alt+f3. They work on the command line.
But in GUI it just loop over and over, keeps on asking for user name and password.