We are migrating from Exchange 2003 to 2010. A month ago I brought the 2010 server online (CAS, Hub Transport and Mailbox on one server). I configured the send connector to send to our extranal spam filter host using a smart host. I swear I tested interent bound mail flow and it was working. THe past month I have been configuring our mobile device management servers to work with Exchange 2010.
This week I finally migrated my first live mailbox (my personal) and everything appeared to be ok until I sent an internet bound email. I can send/receive internal emails across servers ok. I can receive internet email ok. When I sent something external to no matter what domain I try, the mail gets stuck in the queue with error:
451 4.4.0 Primary target IP address responded with: "554 No SMTP service here (Mode: normal)." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts.
On my send connector, I added the FQDN for my mail server (mail.mydomain.org) (that field had been left blank). Address space: SMTP *, 1. Network: Route thru smart host and the host info was copy/pasted from my 2003 connector so no spelling mistakes. I also tried "use the external DNS lookup..." both checked and unchecked. And source server is listed as my 2010 exchange server.
When I try to telnet to port 25, I get error 550 5.7.1 unable to relay
I have been chasing this issue down for 3 days with no results. Any input would be appreciated.