Inside Windows Product Activation

Product ID

The Product ID consists of five groups of decimal digits, as in

AAAAA-BBB-CCCCCCC-DDEEE

If you search your registry for a value named 'ProductID', you will discover the ID that applies to your installation. The 'About' window of Internet Explorer should also yield your Product ID. You can also find the Product ID by right-clicking the icon "My Workplace" and choosing "Properties".