[Blind-sysadmins] strange message

I recently added a client computer to the domain. Now, whenever the person logs on, a message pops up that says fAIL Note the case of the letters. there is absolutely nothing else on the screen. I have performed numerous searches, but none of the search engines will let me do a case sensitive search. Does anyone have any ideas where this message might be coming from, and how to eliminate it? Thanks. Phil