Migrating from Gsuite to Office 365 Migrated accounts cant send email to domain users

New Contributor



We are currently trying to migrate our users from Gsuite to Office365. We own our domain name and it is registered with a 3rd party. I created an endpoint on Office 365


Using the IMAP migration tool i was able to successfully migrate accounts over to the Office 365. 


However, the migrated accounts are unable to send mail to users that have not yet been migrated over to office 365. They can send emails to or but not to the 


Do i need to migrate all users and then update MX for this to work? I have a large amount of users was trying to do this in batches if possible. 


Thank you for your assistance much appreciated!



6 Replies
Have you tried to change in EXO the domain configuration from Authoritative to "Internal Relay"
If your MX record is pointing to Office 365, then you need to change the accepted domain from authoritative to internal relay and also to create a connector to send the emails from your O365 tenant to Google.

Hi Victor, 


Is it possible to keep the MX records pointed at google and configure it so that it relays the emails to office 365? 


The reason why i ask is that we would need enough time to migrate all of the mailboxes before we can cutover. and i would like to ensure that the users that have not been migrated can still send and receive emails. 


Thank you for your response 

I'm not sure what you can do on Google's side, I don't have any experience with it.
best response confirmed by pletendre (New Contributor)
On the Microsoft 365 Roadmap there is this feature:

Google G Suite to Office 365 migration

We've heard the feedback and we're excited to announce the new G Suite migration experience which will allow you to directly migrate email, calendar and contacts from Google G Suite to Office 365! Our highly secure solution ensures your data is directly migrated to Office 365, with no resting points along the way. We're also adding support for migrating mailbox in batches.

I'm not sure exactly when it will be generally available, but if you contact O365 support you might get permission to use the preview.

Thank you Victor!
Yes this is exactly what we would need, i will try to contact them. thank you for your assistance, much appreciated!