RPC Client Access service crashes when you use Outlook in ANSI online mode in an Exchange Server 2010 environment

Assume that your DisplayName property is blank in a Microsoft Exchange Server 2010 environment. Additionally, assume that Microsoft Outlook is running in ANSI online mode, and you have an online profile to receive email messages. In this situation, the Microsoft Exchange RPC Client Access service (Microsoft.Exchange.RpcClientAccess.Service.exe) crashes. Therefore, you cannot access your mailbox. Additionally, the following event is logged in the Application log on the Client Access server:

Time: Time
ID: 4999
Level: Error
Source: MSExchange Common
Machine: Computer
Message: Watson report about to be sent for process id: ProcessID, with parameters: E12, BuildType, Version Number, M.E.RpcClientAccess.Service, M.E.RpcClientAccess.Handler, M.E.R.H.HandlerObjectHelper.DoesEncodingUseFallbackCharacters, System.ArgumentNullException, xxxx, Version Number.
ErrorReportingEnabled: False

This issue occurs because a System.ArgumentNullException exception occurs in the DoesEncodingUseFallbackCharacters function.

To resolve this issue, install the following update rollup:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information about the RPC Client Access service, go to the following Microsoft website: