Process %1 (PID=%2). An internal memory cache error occurred. A hash table iterator is no valid. This event can be caused ...

Process %1 (PID=%2). An internal memory cache error occurred. A hash table iterator is no valid. This event can be caused by internal memory issues. You may be able to resolve this event by restarting the Microsoft Exchange Active Directory Topology service. If the error persists, restart the Exchange server that logged this event.