A product key is a code that's used to activate Windows. Activation helps verify that Windows hasn't been used on more PCs than the Microsoft Software License Terms allow. This is a way that Microsoft can ensure they are able to maximize their revenue and force PC owners to pay their license fee for each individual computer.
Since Windows version ( 98 ? ) the product key is typically on a card inside the box that the Windows DVD came in—or in an email that shows that you bought Windows. It looks like this: PRODUCT KEY: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. If you bought a PC with Windows preinstalled, they key might be on a sticker directly on the computer case or laptop.
Windows 8 PCs now embed their product keys in the BIOS. Microsoft has required manufacturers accommodate this new anti-piracy tactic of storing the key in encrypted format within the bios. Newly built machines that come preloaded with Windows 8 won't have a COA (Certificate of Authenticity) sticker attached to the machine.
See Also:
- Windows Custom Loader, Installer, and Activation Resource
- Windows Genuine Advantage
- Windows XP 30 days left for activation
- Microsoft Windows Installation Keys
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