My friend often emails me mp3s as attachments in mail, and they always come through with no problems. Today, however, he sent an mp3 and that particular email account hangs; the little timer icon just spins and spins. I have to force quit Mail, and every time I restart, an old message from my mom pops up as if newly received. I'm not sure whether the hung message is blocking all subsequent messages on my Mac (I'm currently away from my Airport), but I don't think so.

I can retrieve all the messages on the server (including test messages I sent after the problem started) using my Yahoo! Web mail account, but can't delete anything from the server. Deleting via Mail preferences doesn't work (because the message is not marked as received). Repairing permissions and restarting didn't work.

Is there any way to refuse/reject an incoming message? Can my friend (who uses a .mac mail account) recall or unsend the message? FYI: My friend and I each have Thawte certificates so our emails are encrypted.

I'm using Mail 2.3.1 with a POP account on an iBook G4 running 10.4.11.

Thanks for any and all help.