Recently I changed the A records from my isp (and so pop3 mailboxes) to my fixed IP of our organisation exchange server.
Everything looks fine until, for a reason i don’t understand, i received to some sent e-mails (not all e-mails) the following error message:
[email protected]’ on 01/12/2006 11:33
You do not have permission to send to this recipient. For assistance, contact your system administrator. … Sender IP must resolve>