I have installed Zimbra on my server. We have a registered domain with our ISP and we have established mail relaying for our domain between ou ISP mail server and ours.
We are successfully receiving emails but all outgoing emails are bounced by the ISP MTA with the message : 579 message content is not acceptable here (in reply to end of DATA command)
Our ISP is complaining about the fact that emails Mesage-ID is in the form of email@example.com and it wants to be firstname.lastname@example.org
Does anyone have an idea on how to resolve that ?