I have a current domain set up running exchange 2000 with mail working fine. I just set up a new domain running exchange 2003 however when I migrate a user to the new domain disable their old account and mailbox connect them to the new server and someone attempts to email them from the old domain they get an undeliverable message with no such mailbox existing. It appears if exchange cannot match an address against the GAL it doesn't consider it an internal address. I believe I can create a routing group with an SMTP connector to the new Exchange server but can't seem to get it to work. Can anyone advise how this should be done?
TIA
TIA