I guess like a lot of IT professionals I provide a lot of informal IT support for friends, family and local organisations. Usually it’s sorting out minor problems, giving a bit of advice, but over the past couple of weeks I’ve had two Windows 7 computers come up, quite separately, with exactly the same problem.

In both cases the main user account on the PC has suddenly started coming up with an error “The User Profile Service failed the logon. User Profile cannot be loaded.” when the user tries to log on, at which point the user is dumped back to the log on page – either a log on box or list of users depending on what has been configured. The users affected don’t remember anything unusual – the previous time they used the account nothing untoward happened, and both PC’s had up to date virus and malware protection installed.

The other user accounts on the PC are unaffected, and going in as an administrator the problem account still seems to exist, and passwords can be reset, but the user can still not log on to their account.

Having had a trawl through the Microsoft Knowledge base there is an article that . Following the first set of instructions for fixing the problem in both cases the registry entry for the real user profile has been renamed to .bak, and a duplicate created pointing at the temporary folder. Removing the duplicate and renaming the .bak back to the original SID name, and then resetting the RefCount and State values back to 0 solves the problem, so it’s pretty easy to solve. However it’s curious that two PC’s have gone down with an identical problem within a couple of weeks of each other, so has anybody else come across the same problem?