BUG: You receive an "Unhandled Win32 exception" error message you use the Just-In-Time (JIT) debugger


When you use the Just-In-Time (JIT) debugger, you may experience the following symptoms:
  • You receive the following error message:
    "Just -In-Time Debugging Handler and CLR Remote Host: An exception 'unhandled win32 exception' has occurred in process 'processID'. However, Visual Studio 7 just-in-time debugging has failed. Would you like to try debugging with the previously registered debugger (msdev path/msdev.exe)?"
  • You receive an error message and the JIT Debugger does not start.


This problem is because the absolute path of the shell resides in the registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\shell with a value c:\windows\explorer.exe or c:\winnt\explorer.exe.


Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
To resolve this problem, modify the value of the registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\shell with a value explorer.exe.


Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

More Information

Steps to Reproduce the Behavior

  1. Verify that the Registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\shell value is eitherc:\windows\explorer.exe or c:\winnt\explorer.exe.
  2. Right-click Taskbar, and then click
    Task Manager.
  3. In the Task Manager window, click the
    Processes tab.
  4. Select Image Name from the list that you want to debug. For example, if you want to debug on a notepad, select
    Notepad.exe from the list.
  5. Right-click the image that you selected, and then click
    Debug. You may receive the following warning message:
    "WARNING: Debugging this process may result in loss of data. Are you sure you wish to attach the debugger?"
  6. Click Yes. The error message that is mentioned in the "Symptoms" section of this article is displayed.
To resolve this problem, follow these steps:
  • Change the registry key value to explorer.exe, and then repeat steps 4, 5, and 6 from the "Steps to Reproduce the Behavior" section earlier in this article. Verify that JIT Debugger starts.
  • You can also start JIT Debugger from a Microsoft Visual Studio command-prompt window. To do this:
    1. Locate the Vs7jit.exe file in the C:\Program Files\Common Files\Microsoft Shared\VS7Debug folder.
    2. At the command prompt, type vs7jit -p
      Process ID of the application you want to debug
      , and then press ENTER to start the debugger.

Article ID: 811191 - Last Review: Mar 25, 2008 - Revision: 1