This post featuring a technical look at how to use MX records to enable inbound messaging. MX stands for Mail Exchange, and a single domain can have multiple MX records. MX records are entries in DNS that specify the mail server addresses that you want email messages sent to your domain to be delivered to.
The video below explains more about MS records and how configuration works with your domain. MX records are important when in a coexistence like Microsoft Online Services. MX records determine whether email messages get delivered to the on-premise mail system or BPOS.
The video concludes by walking us through how to enable inbound messaging via MOAC.