Hi, I am running zimbra for more than 5 years, and recently I receive the following error for some important places such as ubc university in canada.
host mailer.chbe.ubc.ca[184.108.40.206] said: 554 5.7.1
<alumni.iut.ac.ir[220.127.116.11]>: Client host rejected: Access denied (in
reply to RCPT TO command)
My mail server Ipaddress is: 18.104.22.168
zimbra is installed on mta.iut.ac.ir
I have more than 15 virtual domain such as cc.iut.ac.ir.
I have one mx and A record for mta.iut.ac.ir
and A record for all subdomains.
would you please let me know what is wrong with my config that I get above error.