How to Remove Malware from Your PC — Step-by-Step Guide

Signs Your PC Has Malware

Watch for these warning signs: PC running unusually slow, random pop-up ads, browser homepage changed, unknown programs installed, high CPU usage when idle, files encrypted or missing, antivirus disabled without your action.

1. Boot into Safe Mode

Safe Mode starts Windows with only essential drivers, preventing malware from loading. Hold Shift while clicking Restart, then go to Troubleshoot → Advanced options → Startup Settings → Restart → Press 5 for Safe Mode with Networking.

2. Run Windows Defender Full Scan

Open Windows Security → Virus & threat protection → Scan options → Full scan → Scan now. A full scan checks every file on your system and takes 30-60 minutes. For stubborn malware, use "Microsoft Defender Offline scan" which runs before Windows loads.

3. Use Malwarebytes (Free)

Download Malwarebytes free version. Install and run a full scan. Malwarebytes excels at finding malware that Windows Defender misses, including PUPs (Potentially Unwanted Programs), adware, and browser hijackers.

4. Manual Removal

Open Task Manager (Ctrl + Shift + Esc) and look for suspicious processes with high CPU usage. Open msconfig and check the Startup tab for unknown programs. Uninstall suspicious software from Settings → Apps. Check C:\Users\YourName\AppData for unknown folders.

5. Clean Your Browser

Malware often targets browsers. Reset each browser to defaults: in Chrome, go to Settings → Reset settings → Restore to defaults. Remove unknown extensions. Clear your browser cache and cookies. Consider blocking ads to prevent malicious ads.

6. Prevention Tips

Keep Windows updated — patches fix security vulnerabilities. Don't click suspicious links in emails or messages. Download only from official sources. Use a strong password for all accounts. Enable Windows Defender real-time protection. Backup regularly to recover from ransomware.

Frequently Asked Questions

Is Windows Defender enough?

For most users, yes. Windows Defender has improved significantly and scores well in independent tests. Adding Malwarebytes as a second-opinion scanner provides extra protection.

Can malware survive a factory reset?

Most malware is removed by a factory reset. However, some rootkits can survive. A clean Windows installation from USB media is the most thorough approach.