When using the Active Directory Migration Toolkit, you may receive an error that a user cannot be moved while they have child leaf objects. This is usually due to the user tying a device to their Exchange account via ActiveSync.
To solve this, make sure you have the Support Tools for Windows Server installed. Open up ADSI Edit (adsiedit.msc), and browse out to the user object.
Under the user container will be another container, ExchangeActiveSyncDevices. Select it, and you’ll see a list of all associated phones for the user on the right pane.
Delete the phones one at a time (right-click, Delete). Once all the phone objects have been deleted, you can then delete the ExchangeActiveSyncDevices container.
Once this is done, you should have no more problems moving the user with ADMT.
I was trying to finish migrating to a new Exchange server, and was running both machines in parallel. Everything had been moved from the old server except for the Recipient Update Services. When I attempted to move one of the services to the new server, I received error code 0xC0070560, “The specified local group does not exist.” This error code conveniently does not exist in Microsoft’s knowledge base.
Apparently during some other server and Active Directory moves, the Exchange Enterprise Servers group in the Users OU of the root domain was changed to a Universal security group. After changing the Exchange Enterprise Servers group back to Domain Local, I was able to point the recipient policy at the new server and proceed with the uninstall on the old server.