Postfix - Community Help WikiPostfix is the default Mail Transfer Agent (MTA) for Ubuntu. It is in Ubuntu's main repository, which means that it receives security updates. This guide explains how to install and configure postfix and set it up as an SMTP server using a secure connection. What is a Mail Transfer Agent In other words, it's a mail server not a mail client like Thunderbird, Evolution, Outlook, Eudora, or a web-bas
