Patches are code updates that manufacturers provide to prevent a newly discovered virus or worm from making a successful attack. From time to time, manufacturers combine patches and upgrades into a comprehensive update application called a service pack. Many devastating virus attacks could have been much less severe if more users had downloaded and installed the latest service pack.

Windows routinely checks the Windows Update website for high-priority updates that can help protect a computer from the latest security threats. These updates include security updates, critical updates, and service packs. Depending on the setting you choose, Windows automatically downloads and installs any high-priority updates that your computer needs or notifies you as these updates become available.

Updates must be installed, not just downloaded, as shown in the figure. If you use the Automatic setting, you can schedule the time and day. Otherwise, new updates are installed at 3 a.m. by default if the computer is on or in a low power state. If your computer is turned off during a scheduled update, updates are installed the next time you start your computer. You can also choose to have Windows notify you when a new update is available and then install the update yourself.

Because of constantly changing security threats, technicians should understand how to install patches and updates. They should also be able to recognize when new updates and patches are available. Some manufacturers release updates on the same day every month, but also send out critical updates when necessary. Other manufacturers provide automatic update services that patch the software every time the computer is turned on, or email notifications when a new patch or update is released.

To update the operating system with a service pack or security patch, follow these steps:

Step 1. Create a restore point prior to installing an update.

Step 2. Check for updates to ensure that you have the latest ones.

Step 3. Download updates using Automatic Updates or from the operating system manufacturer’s website.

Step 4. Install the update.

Step 5. Reboot the computer if necessary.

Step 6. Ensure that the computer is operating properly.

Windows automatically downloads and installs updates to operating systems by default. However, the updates might conflict with an organization’s security policy or other settings on a computer. The following Windows options allow you to control when software is updated:

To configure Windows Update, use the following path:

Start > All Programs > Windows Update > Change settings

If the user is on a dialup network, the Windows Update setting should be configured to notify the user of available updates, or it should be turned off. The dialup user might want to control the update by selecting a time when the update does not interrupt other network activity or use the limited resources available.

In an enterprise environment, patch management policies detail downloading and testing updates offline before deployment to individual PCs in the network.