...but I can successfully send out externally and send/receive internally. Has anyone any suggestions why this may be happening? A little background: - The domain name (dttheroes.co.uk) is registered with netcom.net.uk - The MX record and (A) record are setup to point at our (static) public IP address (although the MX record is set to send mail to the server smtpgw.dttheroes.co.uk). - The exchange 2K server (sp2) is on interenal server mphexdc.dttheroes.co.uk (not smtpgw.dttheroes.co.uk), however, the firewall (firewall-1) NAT policy has been changed to forward all mail destined for the smtpgw server to mphexdc. - The firewall log shows this is working okay (a hotmail message sent to our email system shows up on the log and confirms mphexdc as a valid address. - And that's about it... the external mail gets lost somewhere and never shows up?! Please help... Thanks