Share via


Error: Debugging Isn't Possible Because a Kernel Debugger is Enabled on the System

When you debug managed code, you might receive the following error message:

Debugging isn't possible because a kernel debugger is enabled on the system

This message occurs when you try to debug managed code:

  • on a Windows 7 or Windows Vistasystem that has been started in debug mode.

  • the application uses the CLR version CLR 2.0, 3.0, or 3.5.

Solution

To fix this problem

  • Upgrade your application to use CLR version 4.0 or 4.5

    —or—

  • Disable kernel debugging and debug in Visual Studio.

    —or—

  • Debug using the Kernel Debugger instead of Visual Studio.

    —or—

  • In the Kernel Debugger, disable user-mode exceptions.

To disable kernel debugging in the current session

  • At the command prompt, type:

    Kdbgctrl.exe -d
    

To disable kernel debugging for all sessions (Windows Vista and Windows 7)

  1. At the command prompt, type:

    bcdedit /debug off 
    
  2. Restart the computer.

To disable kernel debugging for all sessions (other Windows operating systems)

  1. Locate boot.ini on your system drive (usually C:\). The boot.ini file might be hidden and read-only. Therefore, you must use the following command to see it:

    dir /ASH
    
  2. Open boot.ini using Notepad and remove the following options:

    /debug
    /debugport
    /baudrate
    
  3. Restart the computer.

To debug with the Kernel Debugger

  1. If the Kernel Debugger is hooked up, you will see a message that asks whether you want to continue to debug. Click the button to continue.

  2. You might get a User break exception(Int 3). If this occurs, type the following Kernel Debugger command to continue to debug:

    gn

See Also

Concepts

Debugger Security

Other Resources

Debugging Managed Code