Encountered an error while processing Active Directory attributes for user %1. The Active Directory attribute being processed ...

Encountered an error while processing Active Directory attributes for user %1.  The Active Directory attribute being processed was %2.  The error description was %3. This event occurs for a variety of reasons.  First, determine if the user listed above is one that should be enabled for Lync Server.  If not, then this event can be safely ignored.  Otherwise, try to determine why the Lync Server service account encounters this error when trying to access the listed attribute on the listed user object.  Once this problem is fixed, disable and enable the user for SIP to resynchronize him/her.