Supress F1 help launching

[nimaata]

im trying to supress the launching of help files when F1 is pressed, but i havent succedded, this is what i have so far, any ideas?

BOOL CrenamefileDlg::PreTranslateMessage(MSG* pMsg)
{
     if((pMsg->message == WM_KEYDOWN) && (pMsg->wParam == VK_F1))
	 {
         NULL;
	 }
...
}