If you wonder how to create a new Postfix user account, this is how you do it, just type in: useradd -s /sbin/nologin username Then follow by setting up a user password: passwd username

Then create Home Directory with appropriate permissions: mkdir /home/username/Maildir chown username:username /home/username/Maildir chmod -R 700 /home/username/Maildir

And finally restart Postifx: /etc/init.d/postfix restart and other services you're using, example: /etc/init.d/dovecot restart /etc/init.d/saslauthd restart