My sister uses Outlook Express as her email client (POP3)with Cox Cable as the iSP. She is totally overrun with spam, to the point of receiving 50-100 of them daily! Cox says they can't do anything about it and they suggest she purchase spam filtering software. If that will appreciably reduce the problem, she is willing, but she doesn't know which of the many products out there would do the most effective job. Any recommendations?