If you're currently running Windows 10 version 1507, version 1511, version 1607, version 1703 or version 1709 you can expect to receive a notification that states that your device must have the latest security updates installed and then initiates an attempt to update your device.
To learn how to check which version of Windows 10 you have installed, learn how to update to the latest version of Windows, or learn more about the “end of service” status for these versions of Windows 10, see the frequently asked questions.
After you receive the update notification, be sure to leave your PC plugged in and powered on while the download completes. Restart your PC when prompted.
This update is also offered directly to Windows Update Client for some devices that have not installed the most recent updates. If you are a Windows Update for Business customer and wish to prevent a feature update, see Deploy updates using Windows Update for Business.
Windows 10 version 1507, version 1511, version 1607 and version 1703 are currently at "end of service." This means that devices that are running these operating systems no longer receive the monthly security and quality updates that contain protection from the latest security threats. To continue receiving security and quality updates, Microsoft recommends that you update the system to the latest Windows version, Windows 10 version 1809. If your device is having trouble installing the latest version of Windows 10, see Troubleshoot problems updating Windows 10 or connect with a member of our support team.
Windows 10 version 1709 is not yet at "end of service." However, it must be updated to the latest versions of Windows 10 to ensure protection from the latest security threats.