I was working in a lab yesterday that uses mandatory profiles. The computers autologon so they were coming up right away with this error: “The User Profile Service failed the logon. User profile cannot be loaded.” After that it would return to the “Press Ctrl + Alt + Delete keys to login message.” Manually logging into the computer with that same account got the same error message but other domain accounts and local accounts were able to login without error.
To fix the error, I launched RegEdit and navigated to HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionProfileList
Expanding the ProfileList key, I looked at the various subkeys until I found the SID S-1-5-21… entry that was pointing to C:Users[account giving error]. I deleted the entire key for that profile, though renaming it also would have worked, and restarted the computer. The autologon then succeeded without error.
According to Microsoft’s KB article on the issue, this may be the result of deleting a profile folder manually. While I don’t think the folder was deleted manually, there are various Group Policies on the lab to delete user profiles older than XX days and delete cached copies of roaming profiles. The error’s symptoms also align with a policy to not logon with a temporary profile.
Instead of deleting folders in C:Users manually, Microsoft recommends going to Computer properties, Advanced Settings, and User Profiles to delete the profiles using the API, which will also clean up the Registry entry in the ProfileList. I’ll have to see if this error reoccurs to do some more troubleshooting to see if the Group Policy settings might also cause the User Profile Service error.