How to Scan Your Windows PC for Malware Using Built-in Windows Security (Windows 11 & 10)

If you suspect malware on your Windows PC or want to perform routine maintenance, leverage the powerful built-in Windows Security tool—no third-party software required. As cybersecurity experts with years of hands-on experience testing antivirus solutions, we've relied on this reliable feature countless times to keep systems clean and secure.

Formerly known as Windows Defender Security Center, Windows Security (often still called Windows Defender by Microsoft) has evolved dramatically. Independent tests from AV-Comparatives show it blocking 99.7% of threats, rivaling top players like Kaspersky and Avast. With Windows 11's enhanced protections, it's simpler and more effective than ever.

To launch it, search "Windows Security" in the Start menu or navigate via Settings > Privacy & Security > Windows Security, then click Open Windows Security.

Run a Malware Scan on Windows 11

Windows Security runs real-time protection by default, neutralizing threats instantly. For on-demand scans:

1. Go to Virus & threat protection.
2. Click Quick scan for a fast check.
3. For thorough inspection, select Scan options > Full scan to examine all files and programs.

If threats are found, click Take actions to quarantine or remove them.

Keep Windows Security Up to Date

Ensure continuous protection:

• In Virus & threat protection > Manage settings, enable Real-time protection and Cloud-delivered protection.
• Check for updates via Settings > Windows Update > Check for updates.
• Update Microsoft Store apps through the Store's Library > Get updates.

If You Still Have Windows 10

The process mirrors Windows 11. Older builds use Windows Security or Defender Security Center—open via search and follow the same Virus & threat protection steps.

Signs Your PC Might Be Infected

Watch for unauthorized changes like altered browser homepages, search engines, or wallpapers; sluggish performance; unusual heat; or rogue pop-ups. Scan immediately if spotted. Google's malware symptom video is a great visual resource.

If Windows Detects a Threat

Notifications appear in the top-right corner (view via taskbar clock). Legitimate alerts from Windows Security auto-resolve most issues, but verify to avoid fakes mimicking antivirus warnings.

Whitelisting a File

False positives happen. To restore:

• Go to Virus & threat protection > Protection history.
• Select the item, click Actions > Allow.

Caution: Even trusted sources can spread malware. Double-check before allowing. View allowed items under Allowed threats and reverse if needed.

When Things Go Wrong

For stubborn malware, run Microsoft Defender Offline scan via Scan options. It reboots into safe mode for a deep clean.

Our team at I/O Means swears by free Malwarebytes for tough cases—install it preemptively. For ransomware or locks, consult a professional IT expert.

Third-Party Anti-Malware Apps

Windows Security excels at core threats but skips phishing or ad scams. Elevate with suites like McAfee, Norton 360, Kaspersky, or Bitdefender—review independent labs first. Multiple AVs? Windows auto-disables its own when another is active.