I am creating a program for taking screenshots of a game, out of the game. When I press the hotkey it works, but with the open game in fullscreen it does not detect the key.
My code:
protected override void WndProc(ref Message m)
{
    const int WM_HOTKEY = 0x0312;
    switch (m.Msg)
    {
        case WM_HOTKEY:
        {
            if ((short)m.WParam == 1)
            {
                start = DateTime.Now;
                progressBar1.Maximum = 1;
                progressBar1.Step = 1;
                progressBar1.Value = 0;
                DoRequest();
            }
            break;
        }
        default:
        {
            base.WndProc(ref m);
            break;
        }
    }
}
I register the global key using:
RegisterHotKey(this.Handle, 1, (int)KeyModifier.None, Keys.F11);
Help-me :/
SOLVED! Resolved, I managed to fix through this project: http://www.codeproject.com/Articles/19004/A-Simple-C-Global-Low-Level-Keyboard-Hook
Thank you all!
 
                        
The problem with most games (not all of them) is that they use DirectInput (DirectX) and not windows message pump to read keystrokes. I have also written an application using voice recognition that sends keys to games and experienced the same issue which I solved by looking at DirectX keycodes. ref: DirectInput