


In the left pane, navigate to Hybrid and click Enable. From the Exchange Admin Center, launch the Hybrid Configuration Wizard.To synchronize the two environments, take the following steps: To complete your hybrid deployment, you need to configure coexistence between your on-prem Exchange and Exchange Online. How to Set up a Hybrid Exchange/Office 365 Environment Microsoft is working on changing this so that when all of your mailboxes are migrated to Office 365, you can decommission that last Exchange Server on your network, but for the time being, it remains a requirement. This is because of the way the Office 365 system defers some things to on-premises Exchange Server machines some roles that the on-prem machine holds cannot be moved up to Office 365 in a supported way. Keep in mind that when you create a hybrid Exchange environment, you have to leave a single premises Exchange Server machine on your local network for the forseeable future.
