Sending mail from exchange 2003 enterprise, to unknown. Send basic email as in hello how are you they recive it. Send an attatchment like a word doc and get response back stating "5.7.1 smtp;550 5.7.1 Requested action not taken: message refused" with my mail server domain included. If reply to a message from the send (such as reply from hiello how are you ) to doamin and attach doc it is received? Any thoughts?