If you'd like to send e-mails through an e-mail address with your own domain name, you have to make sure that the provider will give you usage of their SMTP server. The aforementioned is the software system that allows e-mails to be dispatched. SMTP is an acronym for Simple Mail Transfer Protocol and it manages all outgoing emails from apps, webmail and contact web forms. Whenever a message is sent, the SMTP server checks with all of the DNS servers globally where the emails for the receiving domain name are taken care of and as soon as it gets this information, it connects into the remote POP/IMAP server to find out if the recipient mailbox is out there. If it does, the SMTP server sends the message body and the receiving server sends it to the mailbox in which the recipient can open it and read it. Without an SMTP server on your end, you will not be able to mail out emails at all.