Microsoft Windows Live OneCare 2.0 System Requirements - Microsoft Windows XP (Home Edition, Professional, Media Center Edition, or Tablet PC Edition) with Service Pack 2 (SP2) or Windows Vista (Home Basic, Home Premium, Business, or Ultimate), Windows Internet Explorer 6 or 7 for Windows XP SP2 or higher, PC with 300 MHz or faster CPU speed, 256 MB RAM, 600 MB free space, 56 kbps or faster Internet connection (broadband recommended), CD or DVD burner, external hard drive, or USB-enabled media or storage device required for bac