As you know already, the license is strictly related to the PC’s hardware components, but you’re still be able to use your old windows 10 license even after you will change the hardware components. Even more, activating the license is even less complicated after you install Windows 10 Anniversary Edition Update.
How to Associate Your Windows 10 License with a Microsoft Account
With Windows 10 Anniversary Edition Update it’s easy to associate your old license (obtained before the hardware change) with Microsoft account. This is going to be an automatic process when you sign in with Microsoft account. But there are people who never signed in with a Microsoft account. If you want to enable this automatic process go to Settings > System & Security > Activation and you will be asked to add a Microsoft account, and make the entire process lot easier.
After this step you will see the “Windows 10 is activated with a digital license linked to your Microsoft Account” message. That’s it, you’re good to go. You can change any hardware component from PC and your license is still valid.
How to Activate Your Windows 10 License After a massive Hardware Change
When you are going to reinstall Windows 10 after a massive hardware change and I’m talking about the biggest and most important hardware component – motherboard, just make sure you skip the field where it asks for a product key while installing the new operating system.
It’s still unclear how Microsoft hardware activation process works. I know for a fact that just replacing the hard-drive or change the video card would not cause a problem. If you change only a few hardware components in your computer, the Windows 10 should reactivate itself automatically. But if you do change your motherboard in your computer, the Windows 10 may see your computer as a brand new and it may not reactivate the license itself.
Go to Settings > Update & Security > Activation and click on the Troubleshoot section if the Windows 10 automatic activation fails. Sign in with the Microsoft Windows account previously associated with your license. Now you can tell Microsoft that you “changed hardware on this device recently” and you will be able to choose your PC from a list of devices that has been associated with your Microsoft account. Select the one that suits you and move on. Microsoft Documentation explains how this entire process work.
But Why I Can’t Just Use a Simple Product Key ?
Well that’s the $119.99 question. Free Windows 10 license works differently from previous versions of Windows license system. If you buy a new copy of Windows 10, to install it on a PC you’re building yourself you’ll also have a product key to work with.
In this particular case, the product key would serve to activate Windows. There is no way to find your Windows 10 product key if you want to upgrade for free. Simply, there is no key associated.
This free Windows 10 license work entirely different. Instead of issuing a free Windows 10 License for your PC, it will associate a unique ID that will work directly with Microsoft Windows activation servers.
Even if you reinstall the Windows 10 on the same PC, this will be reported directly to Microsoft Windows activation servers. Activation server will give an OK to the activation process and your reinstalled Windows 10 system will be already activated.
This automatic license process will work only if the PC will have the same configuration as you had before the reinstall.