How to setup allow email with hostname in email address?

After perform what @Andy_Wismer’s recommended and study the following post:

It’s finally work after enable the SystemUserRecipientStatus.

config setprop postfix SystemUserRecipientStatus enabled
signal-event nethserver-mail-server-save

But this still not what I want, as I am going to install TWO NethServer
The first one is mail.domain.com, as my mail server, where the MX record point to.
The second one is abc.domain.com, which is used for testing projects and for receiving emails for the project. That’s why I want the domain part of the email address to be @abc.domain.com

Now, I will set the second NethServer as test.abc.domain.com. Then the domain part of the email address will be as @abc.domain.com

Dummy, but work :grinning: :grinning:
Thanks a lot!