Microsoft Defender is a security app that helps people and families stay safer online with malware protection, web protection, real-time security notifications, and security tips.Microsoft Defender is included in a Microsoft 365 Family or Personal subscription and works on your phone (Android or iOS), PC, and Mac.

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There are two ways to open Registry Editor in Windows 10: In the search box on the taskbar, type regedit, then select Registry Editor (Desktop app) from the results.

Under Microsoft Defender Firewall, switch the setting to On.If your device is connected to a network, network policy settings might prevent you from completing these steps. For more info, contact your administrator.

To activate Windows 11 using an internet connection: As Windows 11 will automatically activate if you are connected to the internet, you can confirm your activation status by selecting Start > Settings > System > Activation and looking under Windows.. If online activation fails, first try the activation troubleshooting in Activate Windows.. To activate Windows 11 by phone:

System File Checker is a utility in Windows that checks for problems with files on your computer. To run it, follow these steps: Make sure you've installed the latest updates for Windows, and then restart your machine.

Tip: If you're a Microsoft 365 Family or Personal subscriber you get Microsoft Defender, our advanced security software for Windows, Mac, iOS, and Android, as part of your subscription.Learn more at Getting started with Microsoft Defender.

Published August 2021. This article is intended for users who are not able to upgrade to Windows 11 because their PC is not currently Secure Boot capable.

Repair programs in Control Panel. Select the Advanced options link under the name of the app (some apps don't have this option). On the page that opens, select Repair if it's available.If it isn't available or doesn't fix the problem, select Reset.

The tool may make one or more changes to the installed version of .NET Framework. For example, it may correct the state of Windows Installer on the computer, reset the discretionary access control lists (DACLs) on certain folders, or resolve issues that are related to an invalid or corrupted update registration.