Use the following steps to fix Vista user profile errors:
1. Log in as Administrator.
2. Make a backup of the C:\User folder to make sure you will not lose your data.
3. Open RUN window (Win key +R) and type in “regedit”, hit Enter.
4. Locate the following registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
5. Expand ProfileList and select each of the subkeys below ProfileList one by one till you find the profile belonging to the user who was experiencing the problem. See the image at right for illustration.

click to enlarge
6. Once you’ve found the subkey for the user experiencing the problem, delete that key.
7. Close the Registry window.
8. Restart Vista.
You are done. Now the user will not get the user profile was not loaded correctly error.