To manually download available updates, go to Microsoft Update or in Windows Vista go to your control panel. After your computer has been scanned to see which updates it needs, click the Custom button to find and choose the update you want to install. We recommend you install all High-Priority Security and Critical updates immediately.
We recommend that you get the updates delivered automatically to your PC. When your computer is on and connected to the Internet, the most current security updates are automatically downloaded and installed. To learn how to turn on automatic updating for your particular operating system, see Update your computer automatically.
If you manage your own computer, install updates as soon as they become available. If your computer is part of a managed network, contact your system administrator before making changes.