During the beginning of this past summer, the SSD boot drive in my previous build died, and I've since then put together a new build and got a new OS(Windows 8.1). I saved backups of most files that were on the boot drive, and I have the Windows 7 reinstallation disc(Home Premium 64), but the sticker with the product key written on it is long gone. I read on various forums that the key is encrypted in the registry, but can be recovered with the right programs. If so, can this be done on backup data?