Hi. I have Ubuntu 11.04, Postfix, Dovecot installed. I've noticed when I send mail from user@mydomain (existing virtual user) to non existing user2@mydomain (non existing virtual user), mail is "delivered", folder user2 is created in /home/vmail/mydomain/ with Maildir in it. Sending user doesn't get any message that user is unknown. In mail.log I have found these lines: postfix/pickup: 3A38745BCF: uid=33 from=<user@mydomain> postfix/cleanup: 3A38745BCF: message-id=<firstname.lastname@example.org> postfix/qmgr: 3A38745BCF: from=<user@mydomain>, size=676, nrcpt=1 (queue active) postfix/pipe: 3A38745BCF: to=<user2@mydomain>, relay=dovecot, delay=0.04, delays=0.02/0/0/0.02, dsn=2.0.0, status=sent (delivered via dovecot service) postfix/qmgr: 3A38745BCF: removed When I send mail from email@example.com to non existing user2@mydomain, I get: SMTP error: 550 5.1.1 <user2@mydomain>: Recipient address rejected: User unknown in virtual mailbox table How can I resolve this? When I send from user@mydomain to non existing user2@mydomain I should get similar message. Thanks in advance.