What is a COA? – Dr Memory (XUM Enterprise Ltd)

Short for Certificate of Authenticity, COA is a document included with some software that proves it was purchased legally. A COA often has a unique identification number used to verify the authenticity of the program when it is being installed on the computer. It includes the product key for your version of Windows which is hidden under a scratchable silver surface.

The COA assists you to determine whether the Microsoft software and components, such as media and manuals, are genuine. If your Microsoft operating system software (Windows 8, Windows 10 and other versions) were supplied to you preinstalled on a new computer system by an original equipment manufacturer (OEM), look for the Certificate of Authenticity on the exterior side panel of the computer case.

Your COA is included with the software components and you should keep them in a safe place.

Finding your Windows product key. Systems with no COA sticker.

As of 2018, most if not all systems now use the digital COA method, which means that the product key is now embedded into the system's BIOS permanently. This means that when you re-install windows, it will detect the product key automatically as long as you are using the same original motherboard. These keys are linked to the motherboard and are valid for any system that has that motherboard installed. It is not linked to the computer system as a whole. So for example, if you remove or replace your motherboard, your windows key may no longer be valid since it is technically not the same computer anymore.