A user URI is already being used by another valid user in the database. Resolve the conflict by using a URI that isn't already ...

Lync Server 2010

A user URI is already being used by another valid user in the database. Resolve the conflict by using a URI that isn't already taken, or deleting one of the users from AD.

URI:
%1
The DN of the user whose URI User Replicator tried to replicate is:
%2
This update came from domain:
%3
Cause: Typically caused by having multiple user or contact objects in AD with identical msRTCSIP-PrimaryUserAddress attribute values.
Resolution:
Use a URI that isn't already taken, or delete one of the offending users. You may use Dbanalyze to diagnose the problem.

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