Instructions provided by Microsoft.com

Security updates help shield your computer from vulnerabilities, viruses, worms, and other threats as they are discovered.

Important: To ensure you have all the latest updates available from Microsoft, be sure to visit Windows Update after turning on the Automatic Updates feature. Automatic Updates only downloads future updates. It does not download existing updates available for your computer. (We'll give you the full details in the second half of this Step.)

Turn on the Automatic Updates feature

Click Start, point to Settings, and then click Control Panel.

Double click Automatic Updates.

Click the Automatic Updates tab, and then select Keep my computer up to date.

Select a setting. Microsoft recommends selecting Automatically download the updates, and install them on the schedule that I specify and setting a daily schedule.

Choose Automatically download the updates and install them on a schedule that I specify

Note: You can set the Automatic Downloads feature for any time of day. (To avoid slow-downs, we recommend a time when you will not be using the computer for other Web or e-mail tasks.) If you set up Automatic Updates to notify you, or if you forget to leave your computer on, you will see a notification balloon. Click the notification balloon to review and install the updates.

Click the balloon to install new updates

You will now download all future updates automatically.

Next, get up to date with Windows Update

Here's how you can bring your computer up to date with security updates that are currently available. You can also use these instructions to keep up with the latest non-critical updates:

Go to the Windows Update Web site at http://windowsupdate.microsoft.com.

On the Windows Update site, click Scan for Updates. Windows Update will scan your computer and displays a pre-selected list of critical updates, including security updates and service packs.

Click Scan for updates

Note: To reduce download times, run Windows Update when you are not using your computer for other Internet-related tasks such as reading e-mail or surfing the Web.

n the Pick updates to install click Critical Updates and Service Packs. Windows Update then creates a list of updates that are appropriate for your computer.

Click Review and install updates.

Select updates to install and then click Install Now. You might have to to restart your computer after installing the updates.
ick Review and install updates.

Note: Be sure to go back to Windows Update after installation to check for any additional updates. You might have to do this several times.

Important If you use Microsoft Office, visit the Office Update site to install the latest security releases.