Thank you for your reply Bill.
I found that the setting was currently "smtpd_reject_unlisted_recipient = no"
postconf | grep smtpd_reject_unlisted_recipient
I suppose changing this setting to "yes" will reject the message before AV/AS will scan the message?
Currently the messages are also rejected, but if a virus is included, the admin is still getting a report about this. (that's the message that I want to stop).
According to following threads:
I changed it manually in the file /opt/zimbra/conf/zmmta.cf and rebooted the server. The setting is now modified to "yes".
I tried sending an email to a non-existing email address before and after the change, and there's no difference between the response. In both cases I get a "Undelivered Mail Returned to Sender" message back to my originating email:
Hopefully the virus notifications to the admin account are stopped this way too!
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to <postmaster>
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
<firstname.lastname@example.org>: 550 5.1.1 <email@example.com>: Recipient address rejected: domain.tld
I will update the thread again (as soon as I'm sure) with the result: solved or not working