A product key is a unique code used to activate Microsoft Windows XP. Without a valid product key, you will not be able to use Windows XP. There are a few different ways to check your Windows XP product key.
One way to check your Windows XP product key is to look at the Certificate of Authenticity (COA) sticker that came with your computer. The COA sticker is usually located on the bottom or back of your computer. The product key will be printed on the COA sticker.