admin I have just upgraded Windows 7 to Windows 10. (Straight upgrade, downloading W10 and allowing it to install immediately, rather than using an ISO on DVD). In case I needed to reinstall at a later time, I looked up the Product Key ( although I understand it may not be needed once a computer is \’registered\’ with Microsoft for Windows 10). I used both Nirsoft ProduKey v1.85 and WinkeyFinder v1.75 (and later the beta 2.0), and they displayed a different product key for Win 10, although the product ID was the same in each case. It has left me a bit baffled, and hoped someone could explain this. Thanks for any help.
The free Upgrade results in a generic \’license key\’.The real \’digital entitlement\’ is a hash of your original Win 7 license, and info from your hardware.The reinstall, you do not need to enter a license key.https://support.microsoft.com/en-us/help/12435/windows-10-upgrade-faqHow do I reinstall Windows 10 on my PC?After you upgrade to Windows 10, you can reinstall or do a clean installation on the same device. You won\’t need a product key to reactivate Windows 10 on the same hardware. For more info on how to create your own Windows 10 installation media, see the Microsoft software download website.