If you want to send out email messages through an email address with your own domain, you have to make sure that the company will give you access to their SMTP server. The aforementioned is the software which allows e-mail messages to be sent. SMTP is an abbreviation for Simple Mail Transfer Protocol and it handles all outbound emails from programs, webmail and contact forms. Every time a message is sent out, the SMTP server confirms with all the DNS servers worldwide where the emails for the receiving domain are taken care of and as soon as it obtains this data, it will connect into the remote POP/IMAP server to see if the recipient mailbox is available. In case it does, the SMTP server delivers the e-mail body and so the receiving server delivers it to the mail box in which the recipient can open it and see it. With no SMTP server on your server, you won't be capable to mail out emails at all.