License keys for Windows 7, 8 and 8.1 can be used to activate a new copy of Windows 10 Creators Update, even if Microsoft has "officially" stopped it free upgrade for Windows 10 from summer 2016.
This means that those users you want to update your operating system from Windows 7, 8, and 8.1 to the latest version of Windows 10 you don't need to buy a new license key to activate the new Windows OS, nor do you need to have upgraded before summer 2016 your old ones Windows.
All you have to do is install a new copy of Windows 10 Creators update and type the old Windows 7, 8 or 8.1 license key and enjoy your new operating system.
FYI, when Microsoft launched Windows 10, it allowed users of older versions of Windows a one-year grace period where you could upgrade them to Windows 10 for free. at the end of this time period users found that Microsoft did not disable this feature, and that they were still able to perform a clean installation of Windows 10 using license keys of previous versions.
Microsoft has, in fact, never blocked the upgrade mechanism and has remained so even now with its coming new version of Windows.
However, this does not mean that this solution is legal to get Windows 10, nor does it mean that Microsoft will not prevent or cause you any problems in the future.
