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Q273496: PRB: IIS 5.0 Hangs with Application.Lock and Application.Unlock

Article: Q273496
Product(s): Microsoft Visual Basic for Windows
Version(s): 5.0,6.0
Operating System(s): 
Keyword(s): kbASP kbASPObj kbCOMt kbOSWin2000 kbVBp600 kbWebClasses kbWebServer kbGrpDSASP kbDSuppo
Last Modified: 25-APR-2001

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The information in this article applies to:

- Microsoft Internet Information Server 5.0 
- Microsoft Visual Basic Professional Edition for Windows, version 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 6.0 
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SYMPTOMS
========

When you debug a Visual Basic WebClass application within the Visual Basic
Integrated Developer Environment (IDE) on a Microsoft Windows 2000-based
computer, and you call the Application.Lock and Application.UnLock methods, the
Web server may stop responding (hang).

CAUSE
=====

With the introduction of COM+, Internet Information Server (IIS) 5.0 takes
advantage of the Thread-Neutral Apartment (NA) when you access the Application
object. As a result, when you explicitly call Application.Lock and
Application.UnLock from a component, you encounter a deadlock scenario that
causes the server to stop responding under certain situations.

RESOLUTION
==========

Do not use Application.Lock and Application.UnLock in your WebClass code when
you debug.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Start Visual Basic. In the New Project dialog box, select IIS Application,
  and then click Open.

2. In the Project window, click to expand the Designers folder. Right-click
  WebClass1, and then click View Code from the shortcut menu.

3. Add the following code to the WebClass_OnStart event:

  Application.Lock
  Application("myvar") = "hello world"
  Application.UnLock

4. Save the WebClass.

5. On the Debug menu, click Start to run the WebClass. Internet Explorer stops
  responding, and the page is never displayed in the browser.

REFERENCES
==========

For additional information, click the article number below to view the article
in the Microsoft Knowledge Base:

  Q271787 PRB: Application.Lock and Application.UnLock Causes Server to Hang in
  IIS 5.0

Additional query words:

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Keywords          : kbASP kbASPObj kbCOMt kbOSWin2000 kbVBp600 kbWebClasses kbWebServer kbGrpDSASP kbDSupport kbiis500 
Technology        : kbVBSearch kbiisSearch kbAudDeveloper kbZNotKeyword6 kbiis500 kbZNotKeyword2 kbVB600Search kbVBA600 kbVB600
Version           : :5.0,6.0
Issue type        : kbprb

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