Microsoft defender

On Windows 10 or Windows 11, Microsoft Defender Antivirus is built into the Windows Security app.

To open it and run a scan:

1. Open the Windows Security app:
   • Select Start, type Windows Security, and select Windows Security from the results.
2. In Windows Security, select Virus & threat protection (shield icon).
3. To run a quick check, select Quick scan.
4. For a deeper check, select Scan options, then choose Full scan (or another option) and select Scan now.

To scan a specific file or folder:

1. Open File Explorer.
2. Right‑click the file or folder.
3. Select Show more options (on Windows 11, if needed), then select Scan with Microsoft Defender.

If more thorough checking is needed (for example, if malware is suspected and hard to remove), run Microsoft Defender Offline:

1. Open Windows Security → Virus & threat protection → Scan options.
2. Select Microsoft Defender Offline scan.
3. Select Scan now, save any open files, and allow the PC to restart and scan outside of Windows.

When the scan completes, Windows Security will show whether any threats were found and guide through removal.

References:

• Microsoft Defender Antivirus in the Windows Security app
• Stay Protected With the Windows Security App
• Scan an item with Windows Security
• Run and review the results of a Microsoft Defender Offline scan
• How to start a scan for viruses or malware in Microsoft Defender
• Getting started with anti-malware in Microsoft Defender