<System Root>\Users\<User Name> Example: C:\Users\johnd

- Delete the desired user key. Example: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\S-1-5-21-144906798-413291513-2040660509-5652
- Locate and delete the following user folder:  <System Root>\Users\<Username>\

The user should now be able to log in, creating a new profile.