Windows Genuine Advantage (WGA)

Windows Genuine Advantage (WGA) is an anti-piracy system created by Microsoft that enforces online validation of the licensing of several recent Microsoft Windows operating systems when accessing several services, such as Windows Update, and downloading Windows components from the Microsoft Download Center. WGA consists of two components; an installable component called WGA Notifications that hooks into WinlogonActiveX control that checks the validity of the Windows license when downloading certain updates from the Microsoft Download Center or Windows Update. WGA Notifications covers Windows XP, Windows Vista and current test versions of Windows 7. It does not cover other versions of the Windows NT family, such as Windows 2000 and Windows Server 2003, or the Windows 9xWindows 2000 Professional licenses as well.^[1] and validates the Windows license upon each logon and an family. The ActiveX control however checks

WGA also advertises the latest service pack for Windows XP, which requires manual intervention to disable. Previously voluntary, it became mandatory for use of these services in July 2005.