FIX: A Windows Forms application that uses ActiveX controls may crash, and a null reference exception occurs after you install the .NET Framework 2.0 Service Pack 1

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After you install the Microsoft .NET Framework 2.0 Service Pack 1, a Windows Forms application that uses Microsoft ActiveX controls may crash. When this problem occurs, a null reference exception occurs. Additionally, the following call stack is generated in the Windows Forms application:
System.NullReferenceException: Object reference not set to an instance of an object.      at System.Windows.Forms.AxHost.OleInterfaces.AttemptStopEvents(Object trash)      at System.Threading._ThreadPoolWaitCallback.WaitCallback_Context(Object state)      at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)      at System.Threading._ThreadPoolWaitCallback.PerformWaitCallbackInternal(_ThreadPoolWaitCallback tpWaitCallBack)      at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback(Object state)

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 .NET Framework 2.0 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.


To apply this hotfix, you must have the .NET Framework 2.0 Service Pack 1 installed.

Restart requirement

You do not have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English 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.
File nameFile versionFile sizeDateTimePlatform,173,24823-5-200804:19x86
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More information
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates

Article ID: 949272 - Last Review: 01/15/2015 23:17:00 - Revision: 2.0

  • Microsoft .NET Framework 2.0
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