Use the System File Checker tool to repair missing or corrupted system ...
When critical Windows system files are missing or corrupted, your operating system may begin to malfunction. Common symptoms include Windows features not working properly, system errors, or Windows becoming unresponsive or freezing.
Automatically fix Windows security issues - Microsoft Support
Troubleshoots and fixes common issues with security and malware prevention in Windows.
Windows troubleshooters - Microsoft Support
Get Help has troubleshooters, or diagnostic tests, that can check your system configuration for anything that might be causing issues using your devices. View troubleshooter results. After you run any troubleshooter, Get Help provides details on any findings and suggestions for possible remedies.
Automatically diagnose and repair Windows file and folder problems ...
Some icons in My Computer, in Windows Explorer, on the desktop, or on the Quick Launch Bar change randomly. Troubleshoots and fixes common issues with file and folder operations in Windows.
Troubleshooting Windows unexpected restarts and stop code errors ...
Windows 11 might shut down or restart unexpectedly when a serious problem occurs, causing you to briefly see an error message, such as “Your device ran into a problem and needs to restart.” Windows 11 will then restart automatically.
Repair apps and programs in Windows - Microsoft Support
This article explains how to repair apps and programs in Windows 11 and use Settings to fix common app issues without reinstalling. You can repair some apps and programs if they're not running correctly. Note that you won't see repair, change, or modify options for all apps and programs. Repair options from the Settings page.
Error codes in Device Manager in Windows - Microsoft Support
In this article, we will help you find your error code and suggest what you might try to correct the error. Follow the recommended resolutions for that error code. You may also click the specific error code to get more detail information. Note: This article doesn't contain all error codes generated by Device Manager.
Using System File Checker in Windows - Microsoft Support
Learn how to run System File Checker in Windows to check if your computer has problems with files.
Fix problems that block programs from being installed or removed
First, you'll need to download the troubleshooter. Download troubleshooter. If you see the File Download box when you start downloading, select Run or Open. The troubleshooter provides steps for you to follow. If a program isn't listed in the uninstall options, you'll be asked for that program's product code.
How to start a scan for viruses or malware in Microsoft Defender
Here's how to do that on Windows, Mac, or Android.
Applies To: Microsoft Defender on Android, Microsoft Defender on Mac, Microsoft Defender on Windows