Generating a Hardware-ID on Windows

Question

What is the best way to generate a unique hardware ID on Microsoft Windows with C++ that is not easily spoofable (with for example changing the MAC Address)?

Answer 1

This used to be the CPU serial number but today there are many types of motherboards and this factor is not accurate. MAC address can be easily forged. That leaves us with the internal hard drive serial number. See also: http://www.codeproject.com/Articles/319181/Haephrati-Searching-for-a-reliable-Hardware-ID