Login Screen keeps asking for password

I installed Ubuntu 15.10 on VirtualBox today and while trying to install jdk1.8.0_66, I updated /etc/profile and /etc/environment поля for updating JAVA_HOME и изменчивые PATH.

Even after the above changes, the терминал couldn't recognize the changes, so I decided to restart my VM.

Now the problem is, after restarting, The login screen keeps prompting я for в password. Even if I enter the correct password, it somehow restarts the login screen (The VM does not restart, only the login screen) and prompts я for в password. гm not able to proceed any further from the login screen.

Please let я know how хан I fix this problem! Thanks в lot!