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You might have to perform an authoritative restore if an administrator inadvertently deletes an organizational unit (OU) containing a large number of users. If you restore the server from tape, the normal replication process would not restore the inadvertently deleted OU. Authoritative restore allows you to mark the OU as authoritative and force the replication process to restore it to all the other domain controllers in the domain.
Source:
authoritative restore
In fact, for Authoritative Restore question, you’d better ask for help from Directory Services forum. The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn.
https://social.technet.microsoft.com/Forums/en-US/home?forum=winserverDS
Thanks for your understanding and cooperating.