Note:- This tweak has nothing to do with Windows Product Activation (WPA) and will not allow you to register illegal XP software.
Start Run Regedit
Go to: HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersion
Modify/Create String Value of Data type REG_SZ Named RegisteredOrganization or RegisteredOwner
Setting for Value Data: Modify the Values to Reflect Current Information
Exit Registry / Reboot more:here