Microsoft KB Archive/913937

= FIX: You receive an error message when you create an application domain that repeatedly loads and unloads a Windows Form =

Article ID: 913937

Article Last Modified on 3/23/2007

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APPLIES TO


 * Microsoft .NET Framework 1.1

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SYMPTOMS
When you create an application domain that repeatedly loads and unloads a Windows Form, you receive an error message that resembles the following:

System.ComponentModel.Win32Exception: Class already exists

Additionally, when a Windows Forms control is hosted in Microsoft Internet Explorer, the Windows Forms control will not load in Internet Explorer when you refresh the Web page.



RESOLUTION
A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it 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 1.1 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product 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. 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.



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

You may notice the following stack dump file when you receive the Win32Exception error message: at System.Windows.Forms.WindowClass.RegisterClass at System.Windows.Forms.WindowClass.Create(String className, Int32 classStyle) at System.Windows.Forms.NativeWindow.CreateHandle(CreateParams cp) at System.Windows.Forms.Control.CreateHandle at System.Windows.Forms.Form.CreateHandle at System.Windows.Forms.Control.get_Handle at System.Windows.Forms.Control.SetVisibleCore(Boolean value) at System.Windows.Forms.Form.SetVisibleCore(Boolean value) at System.Windows.Forms.Control.set_Visible(Boolean value) at System.Windows.Forms.Control.Show

Keywords: kbwinserv2003sp2fix kbhotfixserver kbbug kbfix kbtshoot kbqfe kbpubtypekc KB913937

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