"ALT+ keys are accelerator keys and handled differently. Look at WM_SYSKEYDOWN and WM_SYSKEYUP."
thanks for that messages my friend

"Note: I would say it is generally not proper to intercept someone's accelerator/system keys. Trapping and aborting Alt+F4 could annoy a user as that is one way of closing a window." that's way my blockkeyboard sub works only in that form and not in every where if i block the keyboard i can't block the mouse too(or i lose the input lol).thanks for the big information