Hello,
Since I updated our HT/CAS server with the Exchange 2010 SP3 RU2 I got each hour an event entry for ID 4999 (MSExchange Common):
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Watson report about to be sent for process id: 3140, with parameters: E12, c-RTL-AMD64, 14.03.0158.001, M.E.RpcClientAccess.Service, M.E.RpcClientAccess.Parser, M.E.R.PropertyValue.CheckValueTypeOnConstruction, System.ArgumentException, 56ca, 14.03.0158.000.
ErrorReportingEnabled: False
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The only thing I found for that was an issue that was addresses Exchange 2010 RTM RU1 http://support.microsoft.com/kb/977553/en-us and Exchange 2010 SP2 RU1 http://support.microsoft.com/kb/2599663
Are these problems back with SP3 RU2 ?