Hi
Googling the error message will give you a number of options on repairing corrupt user configuration files
Examples here and microsoft web sites
It helps if there is more than one login account
It helps if you have a windows 7 DVD
Or emergency recovery disk or other disk which will allow acces to the hard disk
Suggested starting place
starting PC in safe mode F8
If you can login with admin account
Create new admin user
Schedule chkdsk on c:
Reboot
See if you can login to old then new account
Fixing old account the Procedure is complex so not repeated here
Possible cause of this error forcing shutdown when system appears to have hung corrupting critical user registry files which are in process of being updated
Best of...