also seeing MSExchange Common 4999 errors.
1.
Watson report about to be sent for process id: 22852, with parameters: E12, c-RTL-AMD64, 15.02.1544.004, w3wp#MSExchangeSyncAppPool, MSExchange ActiveSync, Microsoft.Exchange.AirSync.Common.SchemaConverter.Entity.EntityContentProperty.get_MIMEData, UnexpectedCondition:NotImplementedException, e66d, 15.02.1544.004.
ErrorReportingEnabled: False
exData=|exHResult=|exStacktrace=at Microsoft.Exchange.AirSync.Common.SchemaConverter.Entity.EntityContentProperty.get_MIMEData()
at Microsoft.Exchange.AirSync.Common.SchemaConverter.AirSync.AirSyncContentProperty.InternalCopyFrom(IProperty sourceProperty)
at Microsoft.Exchange.AirSync.Common.SchemaConverter.AirSync.AirSyncContent14Property.InternalCopyFrom(IProperty sourceProperty)
at Microsoft.Exchange.AirSync.Common.SchemaConverter.AirSync.AirSyncProperty.CopyFrom(IProperty srcProperty)
at Microsoft.Exchange.AirSync.Common.SchemaConverter.AirSync.FlexibleSchemaStrategy.ExecuteCopyProperty(IProperty srcProperty, AirSyncProperty dstAirSyncProperty)
at Microsoft.Exchange.AirSync.Common.SchemaConverter.AirSync.AirSyncDataObject.CopyFrom(IProperty srcRootProperty)
at Microsoft.Exchange.AirSync.MailboxItemFetchProvider.BuildResponse(XmlNode responseNode)|exTargetSite=MSExchange ActiveSync Microsoft.Exchange.AirSync.Common.SchemaConverter.Entity.EntityContentProperty.get_MIMEData|exSource=|exMessage=|exComplete=
2.
Watson report about to be sent for process id: 22100, with parameters: E12IIS, c-RTL-AMD64, 15.02.1544.004, w3wp#MSExchangeServicesAppPool, M.Exchange.Net, M.E.E.ExDateTime.IncrementDays, System.ArgumentOutOfRangeException, 67f1-dumptidset, 15.02.1544.004.
ErrorReportingEnabled: False
3.
Watson report about to be sent for process id: 22100, with parameters: E12IIS, c-RTL-AMD64, 15.02.1544.004, w3wp#MSExchangeServicesAppPool, M.Exchange.Services, M.E.S.C.D.ToServiceObjectPropertyListBase.AddFromSchemaPropertyList, S.C.Generic.KeyNotFoundException, ad37-dumptidset, 15.02.1544.004.
ErrorReportingEnabled: False
would be good to get this resolved ASAP.