A couple days ago, I was sending large attachments from one computer to another through my Windows Mail. Then I started getting the same error message on both. I have deleted the messages from the outbox, and I do not on the present computer have Norton. I have also tried deleting the pop.att.yahoo.com account, then reinstalling it. I also tried a system restore to the day before this happened. I'm not sure what now to do. Thanks in advance for any advice. Keith