Use the System File Checker tool to repair missing or corrupted system ...
Use the System File Checker tool to repair missing or corrupted system files. When critical Windows system files are missing or corrupted, some Windows features may stop working correctly or Windows may stop responding altogether.
Deploy Windows Malicious Software Removal Tool in an enterprise ...
Use this tool to find and remove specific prevalent threats and reverse the changes that they made (see the "Covered malware families" list in the "Release information" section of KB 890830). For comprehensive malware detection and removal, consider using Windows Defender Offline or Microsoft Safety Scanner.
List of security program cleanup and uninstall tools
Provides links to the uninstall tools and directions for many security programs.
Uninstall or remove apps and programs in Windows - Microsoft Support
There are different ways to remove apps and programs, so if you can't find the one you're looking for, you can try another location. Note that some apps and programs are built into Windows and can't be uninstalled. You can try to repair a program first, if it's just not running correctly.
Remove specific prevalent malware with Windows Malicious Software ...
Use this tool to find and remove specific prevalent threats and reverse the changes that they made (see Covered malware families). For comprehensive malware detection and removal, consider using Windows Defender Offline or Microsoft Safety Scanner.
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 troubleshoot Windows Installer errors - Microsoft Support
The installation file is typically named Autorun.exe or Setup.exe, but this may vary. If you're not sure, check the Readme file in the folder for instructions about how to run the installation process.
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.
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
System Restore - Microsoft Support
With System Restore you can revert your PC's state to a previous point in time. This can be particularly useful when troubleshooting issues caused by recent changes, such as software installations, driver updates, or system settings modifications.