Chosen Solution
So this is a bit of a weird one, I have a Macbook Pro Retina Mid-2014, The Internal LCD of the laptop only displays when it’s running Mac. It will boot up fine into Mac and works 100%, but when i boot into Windows all i have is a black screen unless i plug in an external monitor. (The internal screen stays black and undetected by windows) I believe it could be a driver or software issue, how would i go about putting that to the test?
Have you run the Bootcamp wizard in OS X and created a USB stick with Windows drivers on it? If you haven’t create one, then boot into Windows with the monitor attached, and then install all the drivers.