If you would like to send out e-mails using an email address with your personal domain, you have to make sure that the company will give you usage of their SMTP server. The latter is the software system enabling e-mail messages to be sent. SMTP is an acronym for Simple Mail Transfer Protocol and it deals with all outbound emails from applications, webmail and contact web forms. Every time a message is sent out, the SMTP server checks with all the DNS servers around the world where the emails for the receiving domain name are handled and when it acquires this data, it creates a connection into the remote POP/IMAP server to find out if the recipient mail box exists. If it does, the SMTP server delivers the message body and the receiving server sends it to the mail box in which the recipient can open it up and see it. Without an SMTP server on your end, you won't be capable to mail out messages in any way.