A Windows developer explains how the leaked FCKGW product key for Windows XP Pro worked: it required both a valid Volume Licensing Key and matching volume media containing a hidden encrypted blob called "Microsoft Bob." The key leaked in August 2001 via the warez group Devils0wn, likely from an OEM partner like Dell, and Microsoft later blacklisted it in SP1 and subsequent updates.
A Windows developer recounts how the Windows XP Product Activation system worked, including the use of Volume Licensing Keys (VLKs) for corporate customers. The famous FCKGW key leaked in 2001 when the warez group Devils0wn obtained the volume media ISO before retail launch, likely from an OEM partner like Dell. Microsoft responded by blacklisting the leaked key's Product IDs starting with Service Pack 1.