Worried about viruses on your Windows PC?
Don’t worry — your computer already comes with a free, built-in antivirus tool called Microsoft Defender.
In this beginner-friendly guide, we’ll explain what Microsoft Defender is, how to use it, and how to scan your PC for threats step by step.
What is Microsoft Defender?
Microsoft Defender (formerly Windows Defender) is a free antivirus program included in Windows 10 and 11. It helps protect your PC against viruses, malware, and other threats — no extra downloads needed.
Main Features
- Real-time protection
- Automatic virus scans
- Firewall integration
- No setup required for basic protection
How to Check If Microsoft Defender Is Active
You can follow these steps to make sure Microsoft Defender is running:
- Click the Start button and open Settings.
- Go to Privacy & Security > Windows Security.
- Click Open Windows Security.
- Look for “Virus & threat protection” — if it says No action needed, you’re protected.
How to Scan Your PC for Threats
If your PC feels slow or something seems off, it’s a good idea to run a scan.
Quick Scan (Recommended)
- Open Windows Security.
- Select Virus & threat protection.
- Click Quick Scan.
- Wait a few minutes. Results will show once the scan is complete.
- If threats are found, follow the on-screen instructions to remove them.
Tip: You can continue using your PC during a scan, but it may run slightly slower.
Other Scan Options
- Full Scan: Scans your entire PC (may take over an hour)
- Custom Scan: Lets you choose specific folders or drives
Which one should you choose?
Quick Scan is fine for routine checks. Use Full Scan if you suspect something’s wrong. Custom Scan is useful for USB drives or downloaded folders.
What If a Threat Is Found?
If Microsoft Defender detects a suspicious file, you’ll see a message like “Threats found.”
- Click See details.
- Choose an action:
- Remove: Permanently deletes the file
- Quarantine: Moves the file to a safe location (recommended)
- Allow: Only if you’re 100% sure it’s safe (not recommended)
- Click Start actions to complete the process.
Note: You may be asked to restart your PC to complete the removal.
Do I Need a Separate Antivirus?
For most users, Microsoft Defender is enough for daily protection.
However, if you handle sensitive data or do online banking, using an advanced antivirus may give you more peace of mind.
Important: Don’t run multiple antivirus programs at the same time — it can cause problems.
Stay Safe with These Extra Tips
- Run a Quick Scan once a week
- Keep Windows updated via Windows Update
- Don’t open unknown attachments or download suspicious files
Taking a few minutes to check your security settings can go a long way in keeping your PC safe.
When in doubt, don’t hesitate to ask someone tech-savvy or contact Microsoft Support.
You’re not alone — and Defender has your back.
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💡 Looking for more tips? Check out our full list of Windows Help Guides.
