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Changing the order in which debuggers are called

margo84margo84 Member Posts: 2

Hello everybody!
I understand, when a user-mode program calls DebugBreak, the following possible actions will occur:
1. If a user-mode debugger is attached, the program will break into the debugger. This means that the program will pause and the debugger will become active.
2. If a user-mode debugger is not attached, but kernel-mode debugging was enabled at boot time, the entire computer will break into the kernel debugger. If a kernel debugger is not attached, the computer will freeze and await a kernel debugger.
This issue was discussed in detail in the thread:
I have an application that has its own user mode debugger attached. This application can only function with its user mode debugger. I need to trace this application. I cannot connect a user-mode debugger to it, since it already has its own debugger. Kernel debugging mode also cannot be used, since breakpoints are processed first by the user-mode debugger and the root-mode debugger is not called.
The question arises. Is there any way to change the priority of calling debuggers? I want the kernel mode debugger to always be called first, followed by the user mode debugger (if available).


  • rod_widdowsonrod_widdowson Member - All Emails Posts: 1,266
    edited January 1

    Not the answer to your question but are you aware of the /noumex BCDEDIT setting?

  • margo84margo84 Member Posts: 2

    Thanks for the answer. The option /noumex is intended for a slightly different action. It rather produces the opposite of the desired effect. Moreover: "The /noumex parameter is effective only when there is no user-mode debugger attached to the process"
    So it doesn't suit me.

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