The upgrade process does not necessarily mean you must buy a new Windows license.
The upgrade process does not necessarily mean you must buy a new Windows license.
OEM is linked to your computer. If you assemble a new PC, you’ll need a fresh license. Upgrading is treated like purchasing a new system, though sometimes Windows allows you to keep your existing license. Retail is connected to your account. You can move it across multiple devices as long as the same license applies to one machine.