Mail routing issue after migrating to O365

I migrated users to Office 365 from on-premise Exchange all went well except that when someone from on-premise emails the migrated user using the old email address, the email is not routed at all. But if the address is in the O365 format, the email is delivered to the migrated mailbox in O365. It looked like the onpremise email address is no longer recognize and only the O365 email address is routing email. Is there any settings I should check to make sure that mail routing will take place using the on-premise email address. As mentioned the email address using O365 works fine but not the on-premise email address. No NDR as well. Any suggestions is greatly appreciated.

Regards,

Lotusmail1o
lotusmail1Asked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Vasil Michev (MVP)Commented:
Are you using the same namespace? Where is the MX pointing at? What kind of migration you performed? Do you still have a local mailbox for the user? Check the value of the targetaddress attribute, see where it points.
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
lotusmail1Author Commented:
The author helped me figured out my starting point to investigate my issue. Thanks!
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Office 365

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.