Mail Flow in EOP
Applies to: Exchange Online Protection
Topic Last Modified: 2014-04-14
As an Exchange Online Protection (EOP) customer, all messages sent to your organization pass through EOP before your workers see them. Whether you host all of your mailboxes in the cloud with Exchange Online, or you host your mailboxes on premises (called a standalone scenario), perhaps to continue taking advantage of your existing infrastructure, you have options about how to route messages that will pass through EOP for processing before they are routed to your worker inboxes.
You may want to configure custom mail routing to conform your messaging to a business requirement. For instance, you can pass all of your outbound mail through a policy-filtering appliance.
EOP offers a lot of flexibility in how your messages are routed. The following topics explain steps in the mail flow process.
Set Up Mail Flow Through Exchange Online Protection provides the basic steps to connect EOP with your on-premises mail server.
Configure Custom Mail Flow by Using Connectors introduces EOP connectors and shows how you can use them to customize mail routing. Scenarios include ensuring secure communication with a partner and setting up a smart host.
Test Mail Flow with the Remote Connectivity Analyzer provides instructions for testing that your mail flow is set up correctly.
Manage Accepted Domains in EOP describes how to manage domains that are associated with your EOP service.
If you add subdomains to your organization, your EOP service can help you manage these too. Learn more about subdomains at Enable Email Flow for Subdomains in EOP.