To help make sure that your computer is as protected as it can be, Windows Live OneCare is continually being updated. When your computer is connected to the Internet, Windows Live OneCare regularly checks for program and service updates, and then downloads and installs the updates automatically when they are available. These updates can include new virus definition (A file containing descriptions or templates of the patterns used by known viruses. Also called a virus signature file.) files, updates to the firewall policy (A list of recognized programs that the Firewall uses to decide which programs have automatic access to the Internet. The Firewall policy is updated periodically as part of the automatic process of updating Windows Live OneCare. ) , and other enhancements to the Windows Live OneCare service.

If you have an "always on" Internet connection, updates to Windows Live OneCare will often occur behind the scenes and you might not even notice when an update has happened. During the time that an update is being installed, you might see the Windows Live OneCare icon disappear temporarily from the notification area of your taskbar, then reappear again a moment later. Infrequently, an update will be installed that requires you to restart your computer.

If you have a dialup Internet connection and you haven't connected to the Internet for several days, you might receive a notification telling you that Windows Live OneCare needs to go online to check for updates. In this case, connect to the Internet, and the update will happen automatically.

If you want to make sure Windows Live OneCare is up to date, you can check for updates manually at any time. Just click the Check for updates link on the Windows Live OneCare screen.

The Check for updates task is designed to wait while another task is running. As soon as the backup is finished, your computer will finish checking for updates and will notify you when your computer is up to date. If you want to complete the update task first, cancel the backup.

This can happen if you clicked Check for updates and then disconnected or lost your Internet connection before the Check for updates task was complete. To correct this, connect to the Internet. The Check for Updates link should be enabled again within a few minutes.

Virus definition files are updated as part of the general process of updating Windows Live OneCare. The release date of your current virus definition (A file containing descriptions or templates of the patterns used by known viruses. Also called a virus signature file.) version is displayed on the Windows Live OneCare main display under Protection Plus. To check for new updates manually, see Related Topics.

In addition to automatically updating itself, Windows Live OneCare also monitors and manages high-priority updates (The most important software updates for Windows and other Microsoft programs that should be installed as soon as they become available. High-priority updates include critical updates, security updates, service packs, and update rollups. ) for Windows and other Microsoft programs on your computer.

Software updates are changes to a program that are made after a program has been released, often in response to a security threat. There are several different kinds of software updates, and with the rate of change today the sheer number of them can be confusing. Some updates are more important than others, especially the ones that are related to your computer’s security. Windows Live OneCare is designed to help reduce the confusion by helping you make sure that your computer has all the high-priority updates that it needs for Windows and other Microsoft programs.

When you first install Windows Live OneCare, setup automatically enlists your computer in Microsoft Update (A Microsoft Web site that provides software updates for Windows components and other Microsoft programs.) and changes your computer's settings to download and install updates automatically using Automatic Updates (A Windows feature that works with Windows Update or Microsoft Update to deliver critical and security-related updates as they become available.) . This helps make sure that your computer continues to receive important updates as soon as possible after they are released. As extra protection, Windows Live OneCare also checks your computer for missing software updates during Tune-up. If any missing updates are found, or if your computer's Automatic Updates settings get changed, you receive an Action to Take helping you to correct the problem.

Microsoft Update is a service that allows you to receive security updates for Windows, Microsoft Office, and other programs from Microsoft. Basically, Microsoft Update does all the things that Windows Update does, and more.

Automatic Updates is a service that routinely checks for updates that can help protect your computer against the latest viruses and other security threats. These high-priority updates are available through the Microsoft Update Web site and include security updates, critical updates, or service packs. If Automatic Updates is set to the Automatic (Recommended) setting it also downloads and installs missing updates automatically. Windows Live OneCare makes sure that Automatic Updates is turned on to the recommended setting, and displays an Action to Take if this setting is changed.

For more information about Automatic Updates, click the Windows XP Start menu, and then click Help and Support. Type Automatic Updates in the search box, and then click the green arrow.