POP3 with Outlook 2000 downloading twice

I have a user with Outlook 2000 connecting to our mail server using POP3. No problems, until today. Starting today, she is getting two copies of every email she receives. Claims to have not touched any settings (I have no reason to believe otherwise, she’s not a ‘tinkerer’). There is only one mail account. Nobody else in that office is having this problem. She IS set to “leave a copy of messages on server”, which are removed after two weeks. I’m at a loss. Any ideas? She is running Windows 95 (I know, she reminds me that this is 2003, too. Tell it to the bosses who sign the checks!).