Microsoft will stop old Windows product keys from activating new

Windows 7 and 8 keys still seem to work for now, but that may be ending.

Windows 10/11: Upgrade path with Windows 7 and Windows 8.1 keys no longer works (Sept. 2023) – Born's Tech and Windows World

Microsoft Ends Free Windows 11 Upgrade:See Who Can Upgrade - Venom's Tech

How to Find Your Original Windows 10 Product Key

Is your Windows license legal? Should you even care?

You can no longer activate new Windows 11 builds with Windows 7 or 8 keys - Neowin

Windows Pro doesn't upgrade to Enterprise with E5 license

So you want to generate license keys for old Microsoft products?, by Daniel Gurney

How to Recover Your Windows 10 Product Key - Make Tech Easier

Microsoft support 'cracks' Windows for customer after activation fails

Microsoft quietly rewrites its activation rules for Windows 10

Windows 11 License Activation Using The Command Line Option HTMD Blog