From Microsoft Windows Support Website
Fix a corrupted user profile
If you tried to log on to Windows and received an error message telling you that your user profile might be corrupted, you can try to repair it. You will need to create a new profile
To create a new user profile
Open User Accounts by clicking the Start button Picture of the Start button, clicking Control Panel, clicking User Accounts and Family Safety, and then clicking User Accounts
Then it goes on for half a page about what to do once you get to the desktop that you can’t get to because your user profile is corrupt.
BTW - posting this from Windows7 with no Internet Access. It says so - right there in the bottom corner. I’m NOT on the Internet, therefore this can’t possibly post