Understanding Windows automatic updating

With automatic updating, you don't have to search for updates online or worry that critical fixes for Windows might be missing from your computer. Windows automatically checks for the latest updates for your computer. Depending on the Windows Update settings you choose, Windows can install updates automatically or just let you know they're available. If you didn't turn on automatic updating when you first started using your computer, you can still turn it on now. For more information, see Turn automatic updating on or off.

If you don't use automatic updating, you should check for updates at least once every week. Microsoft typically releases important updates on the second or fourth Tuesday of the month. However, updates could be released at any time.

If you turned on automatic updating, then most security, reliability, and compatibility updates will be downloaded and installed automatically. Many updates, however, aren't installed automatically. This includes optional updates and updates that require you to accept new terms of use. You'll need to go to Windows Update to check for updates that need to be installed manually.

There is no charge to you for the Windows Update service. However, depending on how you are billed for your Internet connection, standard local and long distance phone charges and Internet service charges might apply for the time required to download an update.

It depends on the type of Internet connection you have and the size and number of updates your computer needs. Updates are automatically downloaded behind the scenes when you're online and don't interfere with other downloads. If you disconnect, updates will continue to download in the background the next time you go online.

Windows Update categorizes software updates based on the update's importance. There are three categories for updates: important, recommended, and optional.

Important updates. Important updates help keep your computer more secure and reliable, protecting your computer and your privacy. These updates include security and critical updates, as well as reliability improvements.

Recommended updates. Recommended updates help keep your software up to date and your computer running at its best. If you selected Use recommended settings when you set up Windows Update, then recommended updates will be shown together with important updates. If you selected Install important updates only, recommended updates will be shown together with optional updates. Recommended updates include software updates and new or improved features.

Optional updates. Optional updates include updates and software that you can install manually, such as new or trial Microsoft software or optional device drivers from Microsoft partners.

Windows Update keeps an update history so that you can check which updates were installed and when. For more information, read the article See which Windows updates are installed.

Windows Update will notify you if you need to restart your computer to finish installing updates, and give you the opportunity to restart right away or postpone the restart. If you're away from your computer for an extended period of time, Windows will automatically restart your computer. Windows does this to help make sure all the latest security and other important updates are applied in a timely manner to help keep your computer more secure.

If you're a system administrator and want to control restart behavior, you can use Group Policy to prevent automatic restarts from occurring.

Windows Update contains software tools that detect information about your computer, such as the make and model and the version of Windows and other Microsoft software that your computer is running. Microsoft uses that information to install only the updates your computer needs. For more information, read the Turn automatic updating on or off and Change how Windows installs or notifies you about updates.

Yes. Windows Update will notify you if security and other important updates can't be installed. For more information, see Troubleshoot problems with installing updates.

Windows provides a built-in troubleshooter that can automatically find and fix some common problems with Windows Update.