I have multiple servers on my network receiving emails, and each one is set to receive messages at domain.com, mail.domain.com, and mx?.domain.com (currently running mx1 and mx2; the new ispconfig3 server is designated mx4). Server is Ubuntu, SMTP is postfix. Incoming emails generate the following log: Note that the mailbox email@example.com has been created and will accept emails. So this is a two-part question, and I'm hoping there is an easy answer... A way to tell ispconfig that emails to firstname.lastname@example.org will also be accepted at email@example.com A method of designating that this particular server will also accept emails to all virtual domains that are tagged with this server's mx -- thus emails received for firstname.lastname@example.org and email@example.com would also be accepted. Question #1 is the most important part I am focusing on, since #2 can be worked around with an easy solution to #1. I can post my config files if needed, but I don't believe this is a configuration issue. Postfix seems to be working as instructed (only allowing emails to known addresses), I just can't figure out how instruct it to allow the subdomain aliases.