Windows only: Ever update your system through Windows Update or install a new piece of software, and when the process completes, your system automatically shuts down or reboots? Of course you have. It’s annoying, right? Free application ShutdownGuard addresses this problem by preventing Windows from automatically shutting down, rebooting, or logging off without confirmation. Each time it prevents a shutdown action, you’ll see an alert in your system tray asking if you really want to shutdown. If you do, click the alert. If not, just keep on keeping on. The lightweight ShutdownGuard is a free download, Windows only.