"The User Profile Service failed the logon” error message - Windows 7

1. Go to regedit


2. In Registry Editor,find and then click the registry sub key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList


3. Locate the folder that begins with S-1-5 (SID key) followed by a long number.


4. Click each S-1-5 folder, locate the ProfileImagePath entry in the details pane, and then double-click to make sure that this is the user account profile that has the error.


5. If there are two folders starting with S-1-5 followed by some long numbers and one of them ended with .bak, you have to rename the .bak folder. To do this, follow these steps:


   a.Right-click the folder without .bak, and then click Rename. Type .ba, and then press ENTER.


   b. Right-click the folder that is named .bak, and then click Rename. Remove .bak at the end of the folder name, and then press ENTER.



  c. Right-click the folder that is named .ba, and then click Rename. Change the .ba to .bak at the end of the folder name, and then press ENTER.



6. Double-click the folder without .bak in the details pane, double-click RefCount, type 0, and then click OK.


7. Click the folder without .bak, in the details pane, double-click State, type 0, and then click OK.


8. Close Registry Editor.


9. Restart the computer.


10. Log on again with your account.