Ok, it wasn't an Admin account was it?
I had a problem once similar.
I created a new account - as admin
I had to remove the Admin account first to make it a normal user (of the one i wanted to remove)
then I logged in as the new admin account
removed the old account
Login as a different user. There is a registry key you must delete. Then also delete the profile from the USERS folder on the hard drive.
Click Start → Run → Regedit.
Navigate to the following registry key : HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList.
Under ProfileList navigate to binary key's like this: S-1-5-21-3656904587-1668747452-4095529-500.
As you browse the keys here you will see a different one for each use profile. Be cautious and careful. Deleteing the key will not remove the data. On the users profile you want to delete I'd recommend just renaming first before you delete it. Reboot and test.