I've just setup a mail server on a CentOS dedicated server. I can successfully send email and receive email, using TLS and everything, so that part is perfect.
The problem, however, is that I can't send emails to people from the same server using an email from the same server.
So, email@example.com can't send emails to firstname.lastname@example.org, but email@example.com can send emails to both firstname.lastname@example.org and email@example.com.
I can't send emails from firstname.lastname@example.org to email@example.com.
A snippet from my maillog:
Dec 22 07:58:34 king postfix/smtpd: NOQUEUE: reject: RCPT from mail-qy0-f172.google.com[126.96.36.199]: 550 5.1.1 <firstname.lastname@example.org>: Recipient address rejected: User unknown in virtual alias table; from=<email@example.com> to=<firstname.lastname@example.org> proto=ESMTP helo=<mail-qy0-f172.google.com>
Not too sure what information to give, so let me if you need more info. As I said, I can email email@example.com properly using my firstname.lastname@example.org.
Note: All email addresses are fictional.
EDIT: I should specify that I use Virtualmin. I have the virtual_alias_maps set in my main.cf to
virtual_alias_maps = hash:/etc/postfix/virtual. In the virtual file, I got plenty of entries generated by Virtualmin such as: