Buggish: User Profile Service service failed the logon. User profile cannot be loaded. (Microsoft Vista)

I was called to assist a family friend's mother who ran into an error with her laptop. Here the problem would have been a little more useful if they had told me what the problem was before I arrived there. The problem is that the user received an error the the profile cannot be loaded once they enter their password.

This made it rather difficult to troubleshoot because I cannot log in to figure what information is missing. Unfortunately, this was also the only user created on this machine. So to get into the machine, I had to reboot the system into safe mode. For Vista, this is F8 during the OS load screen.

Once in the OS, I looked up the error which I came across reference-1. I picked the registry fix:
1. F8 in Windows load screen
2. Safe Mode
3. Open to registry location: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\
4. Look for profile that matches the login in question and there should also be a bak version of the key
5. Rename the main key to another name (I added .bad)
6. Rename the backup key without the extension (remove .bak)
7. Reboot, and this fixed my problem

I then created a backup of the registry file (saved in a folder in the documents folder) so that it could be easier for the user to fix this problem in the future:

1. F8 in Windows load screen

2. Safe Mode with Networking

3. Open My Documents

4. Open old computer backup

5. Double click FixUserProfile.reg (although .reg may not show but should be the only file in the folder)

6. Reboot, and this should fix the problem

Worst case if you dont have a problem to work with, below is the keys needed within the registry profile (modified some values to remove identification):

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\S-1-5-21-XXXXXXXXXX-XXXXXXXXXX-XXXXXXXXX-XXXX]

"ProfileImagePath"=hex(2):00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\

  00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00

"Flags"=dword:00000000

"State"=dword:00000000

"Sid"=hex:00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\

  00,00,00,00,00

"ProfileLoadTimeLow"=dword:00000000

"ProfileLoadTimeHigh"=dword:00000000

"RefCount"=dword:00000002

"RunLogonScriptSync"=dword:00000000

Reference

1 - http://answers.microsoft.com/en-us/windows/forum/windows_vista-security/user-profile-service-service-failed-the-logon-user/4ed66b21-c23e-42f1-98b2-706dcf931fae