Windows Defender, now called Microsoft Defender Antivirus, is a built-in security program in Windows 10 and 11 that protects against viruses, malware, spyware, and ransomware. 2. To use it, open Windows Security from the Start menu, where you can access Virus & threat protection, Firewall & network protection, and other security features. 3. Run a manual scan by selecting Scan options and choosing Quick, Full, Custom, or Microsoft Defender Offline scan based on your needs. 4. Ensure real-time protection, cloud-delivered protection, and automatic updates are enabled under Manage settings, and manually check for definition updates when needed. 5. Review quarantined items in Protection history and restore only if certain they are safe. 6. Enable Controlled folder access under Ransomware protection to block unauthorized apps from modifying important files. 7. For most users, Microsoft Defender is sufficient for everyday protection, but consider third-party antivirus for high-risk activities or advanced features. 8. Regularly check Windows Security status, run a full scan monthly, and keep definitions updated for optimal protection.

What is Windows Defender and how to use it

Windows Defender, now known as Microsoft Defender Antivirus, is a built-in security program included with Windows 10 and Windows 11. It’s designed to protect your computer from viruses, malware, spyware, ransomware, and other threats—without needing to install third-party antivirus software right away.

It runs quietly in the background, scanning files in real time, checking downloads, and monitoring system behavior. Microsoft regularly updates its threat definitions, so it stays effective against new and evolving dangers.

How to Access and Use Microsoft Defender

You don’t need to download anything—Defender is already on your PC. Here’s how to use it effectively:

1. Open Windows Security (Where Defender Lives)

• Click the Start menu and type Windows Security.
• Open the app—this is the central hub for Defender and other security features.

Inside, you’ll see sections like:

• Virus & threat protection
• Device performance & health
• Firewall & network protection
• App & browser control
• Device security

2. Run a Manual Scan

Even though Defender runs automatic scans, you can start one anytime:

• In Windows Security, go to Virus & threat protection.
• Click "Scan options" under the "Current threats" section.
• Choose a scan type:
  • Quick scan – Fast, checks key areas (recommended for routine checks).
  • Full scan – Checks all files and running programs (takes longer).
  • Custom scan – Lets you pick specific files or folders.
  • Microsoft Defender Offline scan – Runs before Windows starts, good for deep-rooted malware.
• Click "Scan now".

Tip: If you download a suspicious file, right-click it and select Scan with Microsoft Defender.

3. Check Protection Status and Updates

Defender updates automatically through Windows Update, but you can verify:

• Go to Virus & threat protection → Manage settings.
• Ensure:
  • Real-time protection is On
  • Cloud-delivered protection is On
  • Automatic sample submission is On (helps Microsoft improve detection)
• Under Virus & threat protection updates, click "Check for updates" to manually update definitions.

4. Review Quarantined Items

If Defender detects a threat, it quarantines (isolates) the file.

• Go to Protection history in the Virus & threat protection section.
• Look for items with "Quarantined" status.
• You can review and, if you're sure it's safe (rare), restore or allow it. But be cautious—most quarantined items should stay blocked.

5. Use Controlled Folder Access (Ransomware Protection)

This feature blocks unauthorized apps from changing important files (like documents).

• Go to Virus & threat protection → Ransomware protection → Controlled folder access.
• Turn it On.
• Add folders you want to protect (e.g., Documents, Pictures).
• Only trusted apps (like Office) can modify these files.

If a legitimate app gets blocked, you can add it to the allowed list.

Is Windows Defender Enough?

For most average users, yes—Microsoft Defender has improved a lot. Independent tests (like those from AV-Test and AV-Comparatives) show it scores well in protection, performance, and usability.

But consider third-party antivirus if you:

• Frequently download torrents or visit high-risk sites
• Work with sensitive data
• Want extra features like password managers, parental controls, or advanced firewalls

Still, having Defender enabled is much better than having no antivirus at all.

Basically, just keep Windows Security open occasionally to check your status, run a full scan once a month, and make sure updates are current. It’s simple, free, and does the job for everyday protection.

The above is the detailed content of What is Windows Defender and how to use it. For more information, please follow other related articles on the PHP Chinese website!