How to Detect and Remove Malware in Windows 11

Malware can quietly creep into your system from a malicious website, a fake email attachment, or even an infected USB drive. Once it’s in, it can slow down your PC, steal personal data, or cause unexpected system errors. Fortunately, Windows 11 comes equipped with powerful built-in tools that make detecting and removing malware easier than ever.

In this guide, we’ll walk you through how to scan for, detect, and remove malware from your Windows 11 PC — step by step.

Detect and Remove Malware in Windows

Before getting started, make sure you have an active internet connection to download the latest security updates, are signed in with an administrator account, and have saved any open work since your PC might restart during or after the scan.

Once that’s ready, you can begin checking your system for malware.

Step 1: Run a Quick Scan with Windows Security

Windows 11 includes Microsoft Defender Antivirus, a built-in protection tool that actively monitors your system for threats.

1. Press Windows + S, type Windows Security, and open it.
2. Click Virus & threat protection from the sidebar.
3. Select Quick scan under the “Current threats” section.

The quick scan checks the most common areas where malware hides — like startup folders, temporary files, and system directories. If any threats are detected, follow the on-screen prompts to remove or quarantine them.

Step 2: Perform a Full Scan

If the quick scan doesn’t find anything but your PC still feels suspiciously slow or unstable, it’s best to perform a full system scan.

1. In the Windows Security app, go to Virus & threat protection.
2. Click Scan options.
3. Choose Full scan, then click Scan now.

This deeper scan takes longer but checks every file and program on your hard drive for hidden or dormant malware.

If Defender detects anything harmful, it will automatically move the file to quarantine or prompt you to remove it.

Step 3: Use Microsoft Defender Offline Scan

Some types of malware are deeply embedded and can’t be removed while Windows is running. In that case, you can use the Microsoft Defender Offline scan.

1. Open Windows Security > Virus & threat protection.
2. Click Scan options.
3. Select Microsoft Defender Offline scan and click Scan now.

Your PC will restart and boot into a special recovery environment where Defender scans your system before Windows loads. This allows it to detect and remove stubborn or hidden malware more effectively.

Step 4: Check for Malware with Task Manager

Sometimes malware disguises itself as a legitimate background process. You can check for suspicious activity using Task Manager.

1. Press Ctrl + Shift + Esc to open Task Manager.
2. Click the Processes tab.
3. Look for any unfamiliar or suspicious processes using high CPU, memory, or network resources.

If you find something questionable, right-click it and choose Open file location.

• If the file is stored in a system folder (like C:\Windows\System32) but has an unusual name, search it online to verify legitimacy.
• If you confirm it’s malware, end the process and delete the file after scanning it with Defender.

Step 5: Remove Malware Using Third-Party Tools (Optional)

While Microsoft Defender is excellent, you can add an extra layer of protection using reputable third-party scanners.

Some popular options include:

• Malwarebytes Free
• Bitdefender Free Edition
• ESET Online Scanner

Download and run one of these tools, perform a system scan, and remove any additional threats they find. Avoid installing multiple antivirus programs simultaneously — they can conflict with each other and slow down your system.

Step 6: Update and Patch Windows

Malware often exploits outdated software and system vulnerabilities. To close those gaps:

1. Press Windows + I to open Settings.
2. Go to Windows Update.
3. Click Check for updates and install everything available.

Keeping your system up to date ensures you have the latest security fixes and protection definitions.

Step 7: Clean Up Temporary Files and Restore Stability

Once you’ve removed the malware, it’s a good idea to clear leftover junk files and reset any affected settings.

1. Press Windows + R, type cleanmgr, and press Enter.
2. Select your system drive (usually C:).
3. Check options like Temporary files, Downloads, and Recycle Bin, then click OK.

You can also use Storage Sense under Settings > System > Storage to automatically remove temporary files in the future.

Step 8: Enable Real-Time Protection

Finally, make sure real-time protection is turned on to prevent future infections.

1. Go to Windows Security > Virus & threat protection.
2. Under Virus & threat protection settings, click Manage settings.
3. Turn on Real-time protection, Cloud-delivered protection, and Automatic sample submission.

This ensures Windows Defender continuously monitors your system for new threats.

Wrapping Up

Detecting and removing malware in Windows 11 doesn’t require any special software — the tools you need are already built into the system. By running a full scan, updating your system regularly, and keeping real-time protection enabled, you can keep your PC safe from most online threats.

For extra peace of mind, pairing Microsoft Defender with a trusted secondary malware scanner like Malwarebytes can provide an additional layer of protection. With these steps, your Windows 11 system will stay secure, stable, and free from malicious software.