Windows 10 uses its own unique product key. Understand and Fix Windows 10 Product Key Activation
For more on activation issues, take a look at these articles: Update: This was written for issues when Windows 10 was initially released in 2015. Regardless of this, product activation remains a part of Windows 10. In this article, we take a look at product activation and troubleshooting steps. The most notable being that Windows 10 is free for existing Windows 7, 8/8.1 users for the first year.
