Yes, I had the same problem. Jon told me it only happened to 3-4 people (and two of them are Pediatricians, go figure) I would yell out, "shut down AC, I need to reset." Then would go the the 4 or 5 computers and reset each one.
Thinking back on it I'm surprised I didn't completely corrupt the database with all those database fixes.
My partner became totally frustrated with AC because of that.
I wasn't using fast switching at that time since I think all the computers were Win 2000 (which didn't allow fast switching)
I think that was V 1.36, not sure, but a later version solved the problem.