I recently could not login to my account on an old laptop with Windows Vista and was presented with this message: "The User Profile Service service failed the logon. User profile cannot be loaded." Fortunately, this was easily remedied by following the steps outlined in Microsoft Article 947215 ("You receive a 'The User Profile Service failed the logon' error message"). That article outlines three methods for resolving the issue (fixing the user account profile, copying data to different profile, and deleting the error SID and creating a new profile).
I used the first approach (fixing the user account profile) by following the steps on that article:
- Restart machine and enter "Safe Mode"
- Typically done by clicking F8 while restarting and selecting "Safe Mode"
- Run the Registry Editor (regedit)
- The registry can optionally be backed up before editing it.
- Access "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList" folder and then the "S-1-5" subfolders with really long names and containing ProfileImagePath in registry
- Rename the folder with
.bakto not have that extension and rename the one that started without extenson to have
- Change RefCount's value to zero and change State's value to 0.
After following those steps (which are explained in more detail and illustrated with screen snapshots in the Microsoft Article 947215), closing Registry Editor, and restarting the laptop, I was able to log in again. I took this opportunity to create a separate Administrator account as advised in this Microsoft Community Question.