SMTP 554 Could not find matching PTR and A records for your mail host
Posted on 2008-10-17
Employee trying to send e-mail to a receipient at one particular address, gets Undeliverable message:
We have exchange 2003 server
You do not have permission to send to this recipient. For assistance, contact your system administrator.
<mailserver.company.net #5.7.1 smtp;554 5.7.1 Sender: Please tell postmaster at your system: Could not find matching PTR and A records for your mail host 18.104.22.168>
Just started happening a few days ago, no changes were made to e-mail server or DNS server at all during this time. We host our own e-mail server, our domain is registered is going through dyndns.org, we have our own dns server.