This article will list the proper MX records for Exchange 2013 hosting.
A mail exchange (MX) record specifies the mail servers that handle email for a domain. The records, listed in order of priority, are configured within DNS at the location of where the domain is hosted. When an email is sent to a domain the sender's mail server checks DNS for existing MX records, and then delivers the mail to the first available server on the priority list. It is very important that only servers capable of relaying email to an ITSN mailbox are listed, thus it must either be an ITSN server (as listed below) or a server forwarding mail to an ITSN server. MX records can be created, and prioritized within DNS to modify mail flow at a user's discretion.
Mail records can be created, and/or modified with the administrative tools through a domain provider. If the domain was registered through, or the name servers are pointed to ITSN, the MX records will be configured automatically through the ITSN control panel.
These are general configuration steps, and not necessarily specific to one hosting company, nor potentially applicable to all.
To create mail records for a domain not hosted by ITSN:
If any difficulty is encountered while creating MX records, contact the domain provider for assistance.
Domain Host Specific Instructions
Out of courtesy ITSN has provided a list of common domain providers, and linked to their MX record setup instructions. If the domain provider is unknown, it may be determined using a free whois lookup through mxtoolbox.com.