I bought System Works because of the Norton name. I installed it on my Gateway computer running Windows ME and had nothing but problems with my computer afterwards even after uninstalling the program. I ended up having to uninstall Windows ME and go back to 98, then reinstall ME. I just built a new computer with Windows XP Professional. I only installed System Works Anti-Virus. It caused lock-ups with my new system also. I uninstalled it and things went back to normal. I couldn't recommend Norton to anyone after this experience. Their technical support has much to be desired also.