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outlook referral and mailbox move in hybrid Office 365 and Exchange 2010

Aeroquinn asked
We are looking to do a migration from Exchange 2010 to Office 365. In a hybrid configuration, can we move the mailboxes, or will require an export/import. Question 2, Will the Outlook 2010/2013 clients do an auto-referral to the new mailbox location.

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Most Valuable Expert 2015
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1) Hybrid is all about remote moves, every other method is a simple copy or import/export of the mailbox data.
2) In hybrid - yes, in every other method you have to reconfigure the Outlook profile.
Murali ReddyExchange Expert
Yes, once you are done with domain setup on office 365 and a valid Migration endpoint/MRS proxy is defined at the office 365 end. This is a mandatory requirement to define a internet published onpremise CAS server as the migration end point, else the remote moves throws an exception. Once this is done, you will be ready to do to/fro mailbox movements.

Outlook will try to connect to the autodiscover record Autodiscover-s.outlook.com at the end for the mailbox to connect. if you are ADFs integrated, your ADFS proxy instance need to be published. Please use connectivity analyzer to see whre you are lagging.


let me know for any clarification.


Thanks for the replies. To clarify, this would be similar to an on-premise Exchange migration with the mailbox moves with ADFS.  I have done several exchange migrations in the past, but not an Office 365. Will AD recognize the mailbox is hosted on Office 365 and change the Exchange Server in Outlook, or is this only using the autodiscover record? Does the end result automatically change the Outlook settings? We are trying to figure out if this basic Exchange migration to Office 365 will require a desktop touch, or if it's automatically configured, much like a standard Exchange migration. Thanks again.