A User ID attribute value was changed, deleted, or added for an existing user in the database. Resolve the conflict by restoring ...

Lync Server 2010

A User ID attribute value was changed, deleted, or added for an existing user in the database. Resolve the conflict by restoring the original value or deleting the user from AD.

The DN of the user whose User ID User Replicator tried to replicate is:
%1
This update came from domain:
%2
Cause: Typically caused by manual modification of msRTCSIP-UserId attribute value instead of using management tools
Resolution:
Restore the original value of msRTCSIP-UserId attribute or delete the user from AD. You may use Dbanalyze to diagnose the problem.

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