So most computers sold with Windows have their actual key embedded in the BIOS on the motherboard. Others, which were upgraded to Windows 10, send Microsoft's s

So most computers sold with Windows have their actual key embedded in the BIOS on the motherboard. Others, which were upgraded to Windows 10, send Microsoft's servers their hardware ID, and are activated based on a digital license stored server side. So the generic keys will allow the installer to proceed, but won't actually provide a Windows license... but most computers already have that anyways and will activate themselves when they go online using one of the above ways.