This error had been spotted all the way back to Windows NT. While I'll call it a corrupt profile and Microsoft discusses it at http://support.microsoft.com/kb/947215 I hope you have a backup account to recover the files with.
Again, always keep a spare admin capable account for when this happens. There is no sign that Microsoft or any other company will repair corrupt profiles. All the articles have us move to a new account.
Since this issue has been around over a decade you begin to wonder how long till a nice fix will appear.
Bob
Hi,
When I boot up I get to the sign in page .
When I sign in I get the message: User Profile Service Failed To Logon and things go round in a loop, I can't get to the Start Menu.
Any suggestions would be gratefully received.
yours,
Stewart
Windows 7 Compaq Computer six months old.

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