I have installed ubuntu 12.04 on VMWARE Workstation. Today I performed some upgrade on ubuntu to install Oracle 11g on it. After installing updates, I restarted it. Since then I am not able to login to ubuntu.

Admin user ID of ubuntu is ubuntu1204. But when I check /etc/passwd from guest login it does not show the user in that file.

While login it does not give any error message as well.

Please help in resolving the issue.