Well, forum search on this didn't return anything noteworthy for me, so here we go. Shell hooking is monitoring window activity, which helps when automating apps. This particular method is pretty similar to installing WH_SHELL hook with SetWindowsHookEx, but instead of callback proc it makes use of window's proc, so GuiRegisterMsg() can be used. How to set it up: First we have to register unique message - RegisterWindowMessage("SHELLHOOK") Then GuiRegisterMsg() the message with a handl