If you are working on something very important and windows keep prompting you to restart your computer so that the updates will take place. This restart prompt step away for a moment and may reboot your computer and cause frustration. Fortunately you can stop it in XP Professional

• Run "gpedit.msc"
• Go to Computer Configuration | Administrative Template | Windows Components | Windows Update
• Then double click ‘No auto-restart for scheduled Automatic Updates installations’ and choose ‘Enabled’ in the settings window.