Microsoft KB Archive/926997

= FIX: Error message when a COM client calls a managed COM component to expose events in the .NET Framework 2.0: &quot;0x80040201 - An event was unable to invoke any of the subscribers&quot; =

Article ID: 926997

Article Last Modified on 12/3/2007

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APPLIES TO


 * Microsoft .NET Framework 2.0

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SYMPTOMS
Consider the following scenario. In the Microsoft .NET Framework 2.0, a managed Microsoft Component Object Model (COM) component is registered for COM Interop. A COM client calls the managed COM component, and the COM client subscribes to the events that the managed COM component exposes. In this scenario, you may receive the following error message:

0x80040201 - An event was unable to invoke any of the subscribers

Note To subscribe to the events that are exposed by the managed COM component, the COM client calls the IConnectionPoint::Advise method and the IConnectionPoint::UnAdvise method. This problem occurs when the COM client calls the IConnectionPoint::Advise method and the IConnectionPoint::UnAdvise method in a particular sequence.



CAUSE
This problem occurs because of an issue with the IConnectionPoint interface implementation in the common language runtime (CLR).



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 Microsoft .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:

http://support.microsoft.com/contactus/?ws=support

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.

Prerequisites
You must have the .NET Framework 2.0 installed to apply this hotfix.

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.

Microsoft .NET Framework 2.0, Itanium-based versions


STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section.



MORE INFORMATION
For more information, 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

Keywords: kbfix kbqfe kbpubtypekc kbhotfixserver KB926997

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