Hotfix KB977020 and hotfix KB973136 are required on the Microsoft Exchange Client Access Server
[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at http://go.microsoft.com/fwlink/?linkid=34707.]
Topic Last Modified: 2010-06-25
The Microsoft® Exchange Best Practices Analyzer examines each Microsoft Exchange Client Access Server (CAS) to determine whether the following software updates are installed:
977020, FIX: An application that is based on the Microsoft .NET Framework 2.0 Service Pack 2 and that invokes a Web service call asynchronously throws an exception on a computer that is running Windows 7
973136, FIX: ArgumentNullException exception error message when a .NET Framework 2.0 SP2-based application tries to process a response with zero-length content to an asynchronous ASP.NET Web service request: "Value cannot be null"
When the Microsoft Exchange Best Practices Analyzer determines that one or more of these updates are required, the tool generates one or more of the following error messages:
This computer requires the update described in Microsoft Knowledge Base article 977020 (http://support.microsoft.com/kb/977020). Please install the required update to proceed.
This computer requires the update described in Microsoft Knowledge Base article 973136 (http://support.microsoft.com/kb/973136). Please install the required update to proceed.
To address this issue, you must install the required software updates on every Exchange CAS server.