The event log resembles the following:
Log Name: Application
Source: MSExchange Common
Event ID: 4999
Task Category: General
Watson report about to be sent for process id: Process ID, with parameters: E12, Build Type, Version Number, M.E.RpcClientAccess.Service, M.Exchange.StoreProvider, M.M.PropValue.MarshalToNative, System.AccessViolationException, XXXX, Version Number.
This issue occurs because a Microsoft Outlook client tries to save a message that has many changes to recipients. Each attempt adds more and more AdrEntry array values and it causes an AccessViolationException exception that triggers the crash.
To resolve this issue, install Update Rollup 10 for Exchange Server 2010 Service Pack 3.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.