How to Remove Malware from Windows Without Third-Party Antivirus
Windows already includes everything you need to remove most malware — if you use the tools in the right order.
Table of contents
Disconnect From the Network First
Before doing anything else, unplug the Ethernet cable or disable Wi-Fi. This prevents data exfiltration, halts command-and-control beacons, and stops the malware from updating itself mid-removal.
Step 1 — Run Microsoft Defender Offline Scan
Settings → Privacy & security → Windows Security → Virus & threat protection → Scan options → Microsoft Defender Antivirus (offline scan). This reboots into a minimal WinPE environment where malware cannot hide behind a running OS — the single most effective built-in tool against persistent threats.
Step 2 — Run the Malicious Software Removal Tool
Press Win + R, type mrt.exe, and run a full scan. MSRT targets prevalent malware families and is updated monthly by Microsoft.
Step 3 — Audit Autoruns
Download Autoruns from Microsoft's Sysinternals page. Run as Administrator, then in Options enable Hide Microsoft Entries and Verify Code Signatures. Anything unsigned, recently added, or with a suspicious publisher should be investigated — right-click → Search Online to verify.
Step 4 — Reset Browser Profiles
Browser-based persistence (malicious extensions, hijacked search providers) survives most antivirus scans. In Edge, Chrome, and Firefox, fully reset settings and remove unrecognized extensions.
Step 5 — Change Critical Passwords from a Clean Device
After cleaning, assume credentials may have been captured. Change passwords for email, banking, and Microsoft account from a different, known-clean device.
When to Reinstall Windows Instead
If you see ransomware activity, kernel-mode rootkit indicators (unsigned drivers in HKLM\SYSTEM\CurrentControlSet\Services), or repeated re-infection after cleaning, do not try to clean further. Back up data, wipe the drive, and reinstall Windows from a Microsoft ISO.
Frequently asked questions
Is it safe to apply these remove malware Windows fixes myself?
Yes. Every step in this guide uses built-in Windows tools or official Microsoft utilities. We recommend creating a System Restore point before making registry or driver-level changes so you can roll back if needed.
Will I lose any data?
None of the procedures in this guide modify your personal files. We still recommend keeping a current backup of important documents — a good habit before any system-level repair.
Do these solutions work on both Windows 10 and Windows 11?
Yes. The instructions cover Windows 10 (22H2) and Windows 11 (23H2 and 24H2). Where steps differ between versions, we call it out explicitly.