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"invalid hook procedure" error when I use SetWindowsHookEx() for WH_KEYBOARD, c++

I am trying to set a global Windows hook for WH_KEYBOARD messages.

I am using the following code:

      hModule = LoadLibrary("C:\\myDlls\\hookDll.dll");
      lpfn = (HOOKPROC)GetProcAddress( hModule,"GetMsgProc");
      hHook = SetWindowsHookEx(WH_KEYBOARD,lpfn,hModule, 0);

When I try to set a hook for WH_GETMESSAGE, everything works fine. However, when I try to set the hook for WH_KEYBOARD, I get the "ERROR_INVALID_HANDLE" error.

Thanks in advance for your help.

Anthony2000

I don't see what's wrong at the moment, but have you compared your code to this Microsoft example:
http://msdn2.microsoft.com/en-us/library/ms644960.aspx

Bengal_Tiger

ASKER

Thats the example I used to write my code. Likewise, the code works as expected when I set a hook for WH_GETMESSAGE. The error is only occurring when I try to set a hook for WH_KEYBOARD.

grg99

What version of windows are you using? Is the program running as a regular user or as Admin?

I suspect Vista might restrict the kinds of hooks you can install.

Bengal_Tiger

ASKER

grg99,

Thanks for the response. I am using Windows XP, and I am logged in as Admin.

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AlexFM

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Bengal_Tiger

ASKER

Alex,

The WH_KEYBOARD_LL hook worked.

Thanks for all the help!

&quot;invalid hook procedure&quot; error when I use SetWindowsHookEx() for WH_KEYBOARD, c++

"invalid hook procedure" error when I use SetWindowsHookEx() for WH_KEYBOARD, c++