TL;DR (English) It might depend on each environment, but in my case, "Right Windows" key is regarded as pressed down. Of course my keyboard doesn't have such a key... So I can't press it. To solve this problem, simulate "R Win" key (VK_RWIN) with some tool. You can create it by yourself using Win32API keybd_event() My guess is that this problem might occur due to the malfunction of keyboards. TL;D