If the steps above don't work, you may need to reinstall Windows. For more info, see Windows 10 recovery options. Describes how to use the System File Checker tool to troubleshoot missing or corrupted system files in Windows 8.1, Windows 8, Windows 7 or Windows Vista.

Microsoft Defender Antivirus is a powerful tool that finds and removes malware from your PC. Here's how to use it in Windows 10 or 11 to scan your PC. Important: Before you use Microsoft Defender Offline, make sure to save any open files and close apps and programs.

This update package is dated February 2017. Anti-malware platform updates for Windows 10 and Windows Server 2016 are typically delivered through updates to Windows Defender. This specific issue only affects those Windows 10 or Windows Server 2016 computers managed by Endpoint Protection. How to obtain this update.

Select Start > All apps and search for the app in the list shown. Press and hold (or right-click) on the app, then select Uninstall. Uninstall in Settings. Select Start > Settings > Apps > Apps & features . Find the app you want to remove, select More > Uninstall.

Action: Remove, Result: 0x00000000 regkey://HKLM\SOFTWARE\MICROSOFT\WINDOWS\CURRENTVERSION\RUN\\v5mpn runkey://HKLM\SOFTWARE\MICROSOFT\WINDOWS\CURRENTVERSION\RUN\\v5mpn file://c:\temp\mpncleantest.exe SigSeq: 0x00002267735A46E2 Results Summary: ----- Found Virus:Win32/MPnTestFile.2004 and Removed!

Antivirus products block malicious software from running on a computer. It is significantly more desirable to block malicious software from running on a computer than to remove it after infection. The tool removes only specific prevalent malicious software.

Select Device details. Select Manage in Windows Security. Select Quick scan. Tips: If you want a deeper scan, instead of selecting Quick scan in step 3, select Scan options and choose the type of scan you want. For the most complete scan, run Microsoft Defender Offline. For more about that see Help protect my PC with Microsoft Defender Offline.

Virus & threat protection in Windows Security helps you scan for threats on your device. You can also run different types of scans, see the results of your previous virus and threat scans, and get the latest protection offered by Microsoft Defender Antivirus. Under Current threats you can:

Antivirus and antimalware software: FAQ. Here are answers to common questions about Microsoft security software, including updates, where to download, and common software errors.

Select Start > Settings > Update & Security > Windows Security > Virus & threat protection. Select Check for updates (or Virus & threat protection updates in previous versions of Windows 10). Under Security Intelligence, select Check for updates. If Windows Security finds a new signature, it will download and install it.