disable alt

[hannibar]

I'm creating a fullscreen openGL program, and I've ran into a problem.
When I press ALT-SHIFT, my screen turns black. Does anyone know how to disable the alt key ?
Ive tried these , but the don't work.
case WM_SYSKEYDOWN:
switch (wParam)
{
case VK_MENU:
return 0;
}

case WM_SYSKEYUP:
switch (wParam)
{
case VK_MENU:
return 0;
}
case WM_KEYDOWN:
switch (wParam)
{
case VK_MENU:
return 0;
}
case WM_KEYUP:
switch (wParam)
{
case VK_MENU:
return 0;
}

[hydro]

i had same problem in directx ... and i realized ...
with alt-shift u might lose exclsive control of ur grafik card...

if someone doing alt shift ... and goes back into ur programm u must initialise all stuff new

in my special case it helpt

if you dont know what happens when alt shift is pressed...

output all messages (log it) and watch out if u can block the ones making the blackscreen

if its opengl issue, i dont know ._.