Windows Genuine Advantage (WGA) is an anti-piracy system by Microsoft which states the authenticity of Microsoft Windows products in a network of some Microsoft operating systems. Windows Genuine Advantage would block the download from the Microsoft Download Center if the original operating system can not be known. WGA protects Windows 2000, Windows XP, Windows Vista and Windows 7, except Windows Server 2003 or Windows 9x family.How to remove wga is as follows
1. Open RegEdit. By the way click on START --> RUN --> type regedit
2. Search in regedit: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion
\Winlogon\Notify
3. Delete the folder 'WgaLogon' and all its contents
4. Restart your Windows XP
5. Go to safe mode by pressing F8 when booting
6. Delete the following files: C: WINDOWSsystem32WgaLogon.dll
C: WINDOWSsystem32WgaTray.exe
C: WINDOWSsystem32LegitCheckControl.dll
Way to the 5th and 6 did not have to be done if it is successful
Disable automatic updates --> right click MyComputer --> Click the Automatic Updates tab --> Select Turn Off. Much for it, hopefully it returned to normal Windows XP as usual.