It isn't Windows that is stopping you but the laptop itself. The laptop may have two additional display ports/hookups in addition to the laptop's own screen but it doesn't mean you can use all three at once. You don't say what laptop, but you will likely find that the video card in it can only support up to two display devices at a time, with one of them being the laptop's own screen.
You want to run three displays off of a laptop, you're going to need an external video device something like this,