I don't think it's the result of the user being "Administrator". I use "Administrator" on my machine at work almost exclusively and never have the problem described. I somehow feel that what described by 525plus in this posting:
http://web.wenxuecity.com/BBSView.php?SubID=computer&MsgID=104011
and his answer followed may solve your problem.
http://web.wenxuecity.com/BBSView.php?SubID=computer&MsgID=104011
and his answer followed may solve your problem.