We're using both Microsoft 365 and Google Workspace at our company, which has led to a bit of a configuration issue. Our previous admin set things up so both platforms are using the same domain (@company.org). While email works fine because our MX record directs traffic to Google Workspace, I'm running into a problem with OneDrive sharing notifications. When I share items, users receive those notification emails in their Outlook inbox instead of their Gmail. From what I've gathered, Exchange is sending these emails as "intra-tenant" messages for speed purposes. Is there a way to configure Exchange to send these notices externally so that they go through the MX record instead? I've tinkered with Exchange connectors and aliases but haven't found a solid solution yet.
3 Answers
It sounds like the main issue is that users should not have mailboxes in 365 with this setup. That might be causing unnecessary complications for you.
Honestly, I'm curious why you're juggling both platforms. Seems a bit complicated!
I recently took over this situation, and here's the quick backstory:
* We utilize Google Workspace for all our email, shared drives, and cloud storage.
* Microsoft 365 is mostly for Entra ID SSO and our SharePoint intranet.
I'm in the process of migrating everything to M365, but there's a lot of groundwork to cover first!
You can set up a connector from Office 365 to your partner organization. Make sure to choose the option that says "only when I have a transport rule set up that redirects to this connector." You'll want it to route through the MX record. After that, create a transport rule to redirect emails to that connector when specific criteria are met, like if the sender is internal and the subject mentions "shared."
Which MX record should I use for the connector? I thought it might be "aspmx.l.google.com" or just our domain "company.org," but even though the connectivity test said it succeeded, it mentioned that the test email was sent without using any connector.
EDIT: Forget my previous question; I realized I didn't follow the instructions closely enough!
Unfortunately, Exchange creates a mailbox for every user as soon as it’s enabled in the tenant. I tried turning off Exchange which did fix the email routing issue, but then I hit a wall because it broke several other features. Even something as essential as Microsoft To-Do needs Exchange to be active.