I have Small Business Server 2003 running exchange on a local domain (i.e. server.domain.local). I seem to be having an email issue sending email to one particular domain. I get the following delay message:
Diagnostic-Code: smtp;450 4.7.1 <server.domain.local>: Helo command rejected: Host not found
Will-Retry-Until: Tue, 15 Feb 2011 08:55:05 -0700
My searches lead me to believe that the receiving email servers may be rejecting (or delaying) email from our domain because the reverse DNS cannot be resolved for the ".local" domain. We are currently using an outside service with DNS and MX records to the server using a ".com" FQDN. This has worked flawlessly for several years, and does not currently affect any other domain email is sent to. Is this a potential cause of the problem, and if so, how can I change the name that the Exchange server supplies in the SMTP header?