When you work with Microsoft Exchange 2010 SP2 with Rollup 4 or a later update rollup that is earlier than Update Rollup 6 installed, you can meet with Event ID 4999.
If you get following events on mailbox server:
Source: MSExchange Common
Date: Date
Event ID: 4999
Task Category: General
Level: Error
Keywords: Classic
User: N/A
Computer: Computer
Description:
Watson report about to be sent for process id: Process ID, with parameters: E12, Build Type, Version Number, ExMSFTE, M.E.Search.ExSearch, M.E.S.Crash.CrashNow, M.E.Common.FailFastException, XXXX, Version Number.
ErrorReportingEnabled: False
Log Name: Application
Source: MSFTESQL-Exchange
Date: Date
Event ID: 64772
Task Category: MSFTESQL Service
Level: Error
Keywords: Classic
User: N/A
Computer: Computer
Description:
The filter daemon process MSFTEFD exited unexpectedly.
Log Name: Application
Source: MSFTESQL-Exchange
Date: Date
Event ID: 1053
Task Category: MSFTESQL Service
Level: Error
Keywords: Classic
User: N/A
Computer: Computer
Description:
The system exception c000010a was raised at 000007FEF99D0F16.
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