Some emails are getting bounced back from external mail servers. We receive error messages like so:
You do not have permission to send to this recipient. For assistance, contact your system administrator. <mailserver.mydomain.com #5.7.1 smtp;551 5.7.1 <email@example.com>... Relaying denied>
I notice we are on a blacklist from a MXToolbox Report. Result showed:
ICMFORBIDDEN LISTED Return codes were: 127.0.0.50 82723 1373
I need to know if the two problems are related, and how do I get off the blacklist?
Exchange Server 2003 SP2
Windows Server 2003 SP2