Use EOP in Hybrid for incoming and outgoing mailflow

Hi,

Below are the highlevel steps-

1. First if you have centralized email flow configured in Hybrid Setup, change it to decentralized email flow. In this options, all your emails excpet your accpted domain will be delivered directly from Office 365 for the users whos mailbox's are moved.

2. Add new internet connector which will be sending email to Internet and disable existing internet sending connector, add smart host entry pointing to MX record of your O365 Domain or change your on-premise send connector which is being used for sending email to Internet and add smart host entry point to MX record of your O365 Domain. You don't need connector for sending email out from Office 365 to Internet and verify the functionality for mail flow. You can use Exchange test connectivity analyzer to verify the header of incoming and outgoing emails.

3. Move your MX record to Office 365 to receive emails.