If you'd like to send out email messages through an e-mail address with your very own domain name, you have to make sure that the provider will provide you with usage of their SMTP server. The latter is the software enabling e-mails to be transmitted. SMTP is an abbreviation for Simple Mail Transfer Protocol and it deals with all outgoing email messages from apps, webmail and contact web forms. Whenever a message is sent out, the SMTP server confirms with all the DNS servers globally where the e-mails for the receiving domain name are handled and when it gets this data, it connects to the remote POP/IMAP server to find out if the recipient mail box exists. In case it does, the SMTP server delivers the email body and the receiving server sends it to the mailbox where the recipient can open it and see it. With no SMTP server on your server, you will not be allowed to send out emails in any way.