A user is able to save his operating system settings to a web server. The user may then download these known, clean operating system over the Internet to the same computer in the future or to a different computer. Or, a user is able to save a known, good restore point to a secure site on the web. If the user suspects that his computer has been compromised by malware, the user downloads this original restore point from over the Internet. The computer is then restored to a known, good state prior to the malware infection. In addition, an entire operating system is present on a USB drive and the user runs his computer from the USB drive. The USB drive is inserted into a publicly-accessible computer. Drivers and network settings from the computer are installed on the USB drive and the operating system on the USB drive then reboots and executes on the computer.