Licenses for Windows come in various flavors from Retail to Volume, but perhaps the most common of all is provided by original equipment manufacturers together with operating systems preloaded on new computers. Since over 80% of the revenues of the Windows Client Division come from sales of Windows on new machines, the OEM licenses are bound to represent the vast majority of EULAs. At the same time, the OEM End User License Agreement is the one offering the least amount of flexibility to customers because it irremediably ties Windows to the PC.

"The original OEM Windows licenses that ships with the PC is bound to that PC. So, if you buy a PC with an OEM Windows license, that OEM Windows license stays with that PC. If you sell the PC, you have sold the OEM Windows license with it. If you donate the PC, you donate the OEM Windows license with it. If you burn and destroy the PC, you burn and destroy the OEM Windows license with it," explained Eric Ligman, Microsoft US Senior Manager Small Business Community Engagement.

Ligman revealed that this situation is also valid for OEM Windows licenses on refurbished computers. As long as the motherboard of a refurbished PC is not changed, customers will not need a new OEM Windows Desktop Operating System license. Since the Windows copy is intimately connected with the PC's motherboard, the OEM license for the operating system will be valid for the refurbished computer as long as that critical hardware component stays in place.

"Just because you wipe the information clean off the hard drive before transferring the PC, it doesn't change the fact that the OEM Windows license stays with it. Because of this, yes, you certainly can reload the original OEM Windows CD back onto the PC since the OEM Windows license is tied to it anyway. Just be sure that when you transfer the PC to the new owner that you also transfer all of the OEM Proof of license components with it as well," Ligman added.