Run a full scan using Windows Security by opening Settings, navigating to Privacy & security > Windows Security > Virus & threat protection, selecting Full scan under Scan options, and clicking Scan now; ensure real-time protection is enabled. 2. Use Microsoft Defender Offline scan by going to Scan options in Windows Security, selecting Microsoft Defender Offline scan, and clicking Scan now to restart and scan before Windows loads, effectively detecting rootkits and deep-seated malware. 3. Manually check for high CPU, disk, or network usage, unfamiliar processes in Task Manager, browser redirects, pop-ups, slow performance, or unexpected ransomware messages, and research suspicious processes online. 4. Optionally use a trusted on-demand third-party scanner like Malwarebytes or HitmanPro to detect threats missed by Windows Security, but avoid installing multiple real-time antivirus programs to prevent conflicts. Keep Windows and software updated, avoid suspicious downloads and links, and maintain regular backups to minimize risks. Using Windows Security regularly, performing offline scans when needed, and employing a secondary scanner if symptoms persist ensures effective malware detection and removal in Windows 11.

If you suspect your Windows 11 PC might be infected with malware, it's important to act quickly. Here’s how to check for and deal with potential threats effectively.

1. Run a Full Scan with Windows Security (Built-in Antivirus)

Windows 11 comes with Microsoft Defender Antivirus (part of Windows Security), which is active by default and regularly updated. It’s a solid first line of defense.

Steps:

• Press Windows I to open Settings.
• Go to Privacy & security > Windows Security > Virus & threat protection.
• Under "Current threats," click Scan options.
• Select Full scan, then click Scan now.

A full scan checks all files and running programs. It takes longer than a quick scan but is more thorough. If malware is found, Windows Security will attempt to remove or quarantine it automatically.

Tip: Make sure real-time protection is turned on (it should be by default). You can check this under "Virus & threat protection settings."

2. Use Microsoft Defender Offline Scan (For Stubborn Malware)

Some malware hides deep in the system and can’t be caught while Windows is running. The offline scan boots your PC into a special environment to catch these threats.

Steps:

• In Windows Security, go to Virus & threat protection > Scan options.
• Scroll down and click Microsoft Defender Offline scan > Scan now.
• Your PC will restart and run a scan before Windows loads.

This scan can detect rootkits and other low-level malware that might evade regular scans.

3. Check for Suspicious Activity Manually

Even with antivirus software, it helps to look for signs of infection:

• High CPU, disk, or network usage with no clear cause (check via Task Manager: Ctrl Shift Esc).
• Unfamiliar processes running in Task Manager.
• Browser redirects, pop-ups, or new toolbars you didn’t install.
• Slow performance or frequent crashes.
• Unexpected password prompts or ransomware messages.

If you see strange processes, right-click them in Task Manager and select Search online to check if they’re legitimate.

4. Use a Trusted Third-Party Malware Scanner (Optional)

While Windows Security is strong, using a second-opinion tool can help catch anything missed.

Recommended free tools:

• Malwarebytes – Excellent at detecting adware and PUPs (potentially unwanted programs).
• HitmanPro – Lightweight cloud-based scanner that works well alongside Defender.

Note: Don’t install multiple real-time antivirus programs—they can conflict. Use these as on-demand scanners only.

Final Tips

• Keep Windows and all software updated.
• Avoid downloading cracked software or clicking suspicious email links.
• Regularly back up your data.

Basically, use Windows Security for routine scans, run an offline scan if you're still unsure, and consider a second opinion from Malwarebytes if symptoms persist. Most threats in Windows 11 are caught early if updates and protection are enabled.

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