I have received a few complaints from people who have been receiving the following error from my zimbra server when sending mail to my account on the Zimbra server:
I have been receiving a lot of mail just fine since i installed zimbra, but the fact that some people seem to receive this error makes me think that the system is actively blocking mail from some senders.xxx.xxx.xxx.xxx does not like recipient.
Remote host said: 553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1)
Giving up on xxx.xxx.xxx.xxx.
I did not add any domain to any blacklist. What can this be?