Setting up Smarthosting for O365

1. Navigate to then sign in with your O365 Global Admin credentials.

2. Once signed in click the Admin button.

3. In the admin center click the Admin Centers drop-down then choose Exchange.

4. In the Exchange Admin Center click Mail Flow then click Connectors.

5. Click the + sign to create a new connector.

6. In the new connector window under From choose Office 365 and then under To choose your organization's email server then click Next.

7. Enter a name and description for the connector then make sure both the "Turn it on" and "Retain internal Exchange email headers" are checked then click Next.

8. If you want to Smarthost all external email Select the button for "Only when I have a transport rule set up that redirects messages to this connector".

9. Click the + sign to enter a server then in the Add Smarthost window enter "" then click Save.

10. Click Next now that is listed.

11. Ensure that "Always use Transport Layer Security to secure the connection" is checked then make sure "Issued by a trusted certificate authority" is selected. Once the settings are confirmed click Next.

12. In the confirm your settings window check your settings then click Next.

13. On the validate this connector page click the + sign then enter an external email address and click OK. Next click Validate on the validate this connector page to send a test message.

14. You should now see a message that says Done! and you can click Close on that window.

15. Finally, click Save on the validation result page to save the connector. (Note: It is still okay to continue if the Send test email tasks says Failed.)

16. If you see a Warning message that says the connector was not validated successfully click Yes to continue.

17. Back in the Exchange Admin Center click on Rules then click the + sign and choose Create a new rule.

18. In the new rule window click More Options at the bottom to reveal all rule options.

19. Give the rule a Name then under Apply this rule if select the recipient > is external/internal > then choose Outside the organization and click OK.

20. Under do the following select Redirect the message to... > the following connector > then choose the connector you created for Smarthosting then click OK.

21. Next click Save at the bottom to save your new Smarthosting rule. Note: new rules typically require at least two hours of propagation time.

22. Congratulations!!! You have successfully setup your Office 365 tenant for Smarthosting.