Posts to Mailman list bouncing- User unknown

[scientist]

I installed ISPConfig 3.0.5.1, with Apache, Postfix, Dovecot on a CentOS-flavor system.

I made the language correction and disabled CGI with domains I am testing for Mailman use.

I can send and receive emails externally and int5ernally with SquirrelMail. I can create Mailman lists from the ISPConfig interface. I can add subscribers through the web and they receive email confirmation requests from mailsituation-request@lists.mydomain.com.

If I click the link, the subscriber is added. However, if I reply, the email is sent back with a permanent fail. I also get a permanent fail if I try to post, using the list@domain.com and list prefix in the subject line. I've tried setting up with non-subdomains as well (mydomain.com).

I get this error in my maillog:

NOQUEUE: reject: RCPT from mail-ob0-f179.google.com[209.85.214.179]: 550 5.1.1 <listname-request@lists.mydomain.com>: Recipient address rejected: User unknown in virtual mailbox table; from=<myemail@gmail.com> to=<listname-request@lists.mydomain.com> proto=ESMTP helo=<mail-ob0-f179.google.com>