I went to the microsoft download site. Then the service pack center. Then the download sp3 from the site file kb936929. Then there was a screen saying Inspecting current installation. Then I got an error screen that said. This service pack cannot be installed on top of the windows xp service pack 3 build currently installed. Uninstall this and then install sp3 file. So I am assuming there is a service pack 3 on the computer now but I cannot find it or I don't know what it is called so I cannot uninstall it. I have looked in add and remove programs, installed windows updates, I have done a search for service pack 3.