Hi im trying to restore and remove windows 8.1 and start a fresh install but when I go to recover in windows it says insert media but when I do that it says the media isn't valid but its the original windows 8 pro upgrade disc so I tried it in boot to remove windows but its saying now unable to reset your pc a required partition is missing is there a way around it to get it back? in the this pc folder there is only the local disc ( C ) nothing else what do I do