"Link" Office 365 to AWS Workmail / SES

Question

I currently use AWS SES and Workmail. I need SES because we need to process specific emails with AWS SNS rules. The other mails are redirected to Workmail.

Now we signed up for O365. I managed to send emails from my O365 account but obviousely I do not receive any once I get an email.

In my opinion I can not point the MX entry to O365 (as SES wouldn't see the incoming mails I guess).

So is there a way to connect O365 Exchange to SES? Or am I getting the whole thing wrong?

Answer 1

Ok I figured it out. Follow those steps if you encounter a similar problem:

1. Set Up Office 365 as your primary Mailserver (inkl. MX Entry). I did not delete the AWS entry, but this one anyway has priority 10, while Microsoft wants Prio 0.
2. Change the spf record to include both aws and exchange.
3. Create a connector in the Microsoft Exchange Admin where you point from Office 365 to external organisation. Define that this connector should only be used when a rule is pointing to it. Include the imap adress of your ses endpoint. Mine was imap.mail.eu-west-1.awsapps.com. Test some emails you are trying to process with aws. Hint: if you fail doing so, create those email adresses as team-email-addresses at office (super strange behaviour, I know).
4. Create a rule, that uses your connector for all email addresses you want to be handled by aws.
5. You are done!

Hope this helps.