The company I work for is running SBS 2003 and we just got a static IP so we began routing emails via DNS since our ISP blocks routing via smarthost. We have an external webhost that uses our domain name, for security’s sake I’ll call it domain1.com, however the internal Exchange has it set up also as domain1.com as the domain. Most of our emails go through no problem but a few emails get blocked with this message
Your message did not reach some or all of the intended recipients.
Subject: TEST
Sent: 4/2/2009 12:58 PM
The following recipient(s) cannot be reached:
‘someone@ic.sunysb.edu’ on 4/2/2009 12:58 PM
You do not have permission to send to this recipient. For assistance, contact your system administrator.
I have a feeling, but could be totally off base, it is because we have an external webhost for hosting our website and their server resolves domain1.com to point to our webhost not our static IP, but we want to use Exchange eventually for all of our company email. How do I resolve this? Would changing the MX record fix this?