Updating to Windows 8.1 from Windows 8
But before you begin, here are some things to keep in mind.
Your files, desktop apps, user accounts and settings come with you. Windows 8.1 and Windows RT 8.1 come with some new built-in apps, and it will update or replace some of your existing built-in apps. Your existing Windows Store apps don't come with you, but once the update is complete, you can reinstall all of these apps at once – or just the ones you want. For more info, see the Reinstalling your Windows Store apps section of this page.
We'll check your desktop apps and devices for you. As part of the update, we check your current desktop apps and connected devices, and let you know what you'll need to do to get them ready for the update, or to get them working again after the update. In most cases, you won't need to do anything – most desktop apps, devices (like printers) and network connections will work normally after the update. If you have particular desktop apps or devices you're concerned about, you can check their compatibility in the Windows Compatibility Center.