Excel Close messages trick

Hello
I am looking for an answer to a question that has been bothering me. My co-workers excel program has a problem. When she closes the program the choices to save the spreadsheet are wrong. I was told this is a registry problem but I can not change the settings without knowing what line of the registry to Nullify. I was told this was a trick that was being played about a year ago and I can’t remember the name. Please help Me

Thanx