If you wish to send out e-mail messages using an e-mail address with your domain name, make sure that the company will give you access to their SMTP server. The latter is the software that allows e-mail messages to be transmitted. SMTP is an acronym for Simple Mail Transfer Protocol and it manages all outbound emails from applications, webmail and contact forms. Whenever a message is sent, the SMTP server checks with all the DNS servers worldwide where the emails for the receiving domain are managed and as soon as it acquires this info, it creates a connection to the remote POP/IMAP server to find out if the recipient mail box is available. In case it does, the SMTP server directs the e-mail body and the receiving server sends it to the mail box in which the recipient can open it up and read it. Without having a SMTP server on your server, you will not be capable to send out emails at all.