How to Reclaim Hard Disk Space after Upgrading to Windows 10 | Techniqued When you upgrade to Windows 10, the set up will keep a copy of existing version of Windows 8.1 so that in case you want to downgrade, set up can use it. If you are finalized on Windows 10, you can remove this and reclaim hard disk space. Stay tuned to Techniqued for the latest in mobile technology and hit that Subscribe button or click the link below: http://www.youtube.com/user/nirmaltv?...