You have a Microsoft .NET Framework 2.0-based Multi-AppDomain application. When you run the application, an infinite loop occurs in the common language runtime (CLR) worker threads. Then, the application stops responding. Additionally, the memory usage of the operating system increases significantly.

Note This symptom occurs for various reasons. The hotfix in this article only resolves this problem for the cause described in the "Cause" section.

This problem occurs because an application domain cannot unload successfully. The CLR does not report this failure to the thread pool where the worker threads are running. Therefore, the thread pool waits indefinitely for the result of the unload operation instead of handling work that is queued by the application domain.

Note Typically, an application domain cannot unload successfully because of a time out.

Note This hotfix was updated on April 20, 2011 to resolve the following known issue:

• After you install security update 2449742 or 2446709 on a computer that is running Microsoft Exchange Server, Microsoft SQL Server, or Microsoft PowerShell, you may experience problems with Exchange Server, SQL Server, or PowerShell-related crashes.
  
  For more information about this issue, click the following article number to view the article in the Microsoft Knowledge Base:
  2540222  (http://kbalertz.com/Feedback.aspx?kbNumber=2540222/ ) Exchange Server, SQL Server, or PowerShell crashes after you install security update 2449742 or 2446709

Hotfix information

A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next service pack that contains this hotfix.

To download this hotfix from the Microsoft Developer Network (MSDN) Code Gallery, visit the following Microsoft website: Note The MSDN Code Gallery displays the languages for which the hotfix is available. If you do not see your language listed, it is because the Code Gallery resource page is not available for that language.

Note Alternatively, you can download this hotfix rollup from the following Microsoft Connect website:

Prerequisites

You must have the .NET Framework 2.0 Service Pack 2 (SP2) or the .NET Framework 3.5 Service Pack 1 (SP1) installed to apply this hotfix.

Restart requirement

You do not have to restart the computer after you apply the hotfix if the files that the hotfix affects are not being used.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English (United States) version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

For all supported x86-based versions of Windows Server 2003 and of Windows XP

For all supported x64-based versions of Windows Server 2003 and of Windows XP

For all supported IA-64-based versions of Windows Server 2003 and of Windows XP

For all supported x86-based versions of Windows Vista SP2 and Windows Server 2008 SP2

For all supported x64-based versions of Windows Vista SP2 and Windows Server 2008 SP2

For all supported IA-64-based versions of Windows Server 2008 SP2

For all supported x86-based versions of Windows 7

For all supported x64-based versions of Windows 7 and of Windows Server 2008 R2

For all supported IA-64-based versions of Windows Server 2008 R2

If this hotfix is not posted for public download (meaning a public URL for this hotfix is not provided in this article), distribution requires technical lead, escalation team member, or manager approval and the following information applies:

• To receive the hotfix, customers must be experiencing the bug that is mentioned in the "Symptoms" section.
• You must track the customers you send this to and supply them with the next service pack when it becomes available (if a service pack is released).

This hotfix is scheduled to be included with Windows Vista Service Pack 3 (SP3), and was included Windows 7 Service Pack 1 (SP1).

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

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base: