a friend has a 4TB harddisk that turned into RAW after upgrading to win10. the drive is a data drive and not an OS drive. i guess, for some reason the drive header got corrupted and that is why win10 shows it as a RAW drive. but when he connects the drive to win7 (the system the drives was conneted to earlier) the drive shows correctly. i wonder, when the drive header is corrupted then win7 should not be able to show its content either .. except when it stores a backup of the header. right? or what could be a reason that the drives shows as RAW in win10 and correctly under win7?