What does the MX record do?

The Mail Exchange (MX) record sets the mail server for your domain name, directing all emails to the correct location and mail server.

If you have your-domain.com, setting an MX record will determine where the mail for [email protected] is sent.  The mail server must be configured to accept email for the domain.

By default, your Heart domain names will have an MX record pointing to the mail. subdomain (for example, mail.your-domain.com). 

If you wish to use an external mail server, you can change the MX record in the Manage DNS section in your Domain Control Panel.