How mailbox permission is handled in exchange server cross forest migration

Question

Hi All, We are migrating our existing exchange 2016 server to a new forest (in Exchange 2019). We are panning to use MS native tool/method to move mailboxes (new-move request). My question is, how the maibox permission- such as full mailbox, send-as, application impersonation are handled in this method. Are the permissions also migrated along with the move request? Any help is really appreciated.. thanks !

Answer 1

Hi @Acloudguy

Based on my test, the delegate permissions would get lost after the migration and you may need to re-assign the permissions.

This TechNet article also discusses this behavior: Mailbox auto-mapping is lost for migrated users after cross-forest migration

To me I would suggest use some scripts to export the permissions before migration and later re-assign permissions.

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Answer 2

@Kael Yao-MSFT that was helpful, thank for your help