The best free antivirus setup for Windows 10 and Windows 11 is the built-in Windows Security combined with on-demand scans from Malwarebytes Free, AdwCleaner, and Norton Power Eraser. Windows Security delivers real-time protection that scores on par with most paid suites, and the free on-demand scanners catch leftover adware, browser hijackers, and stubborn malware without slowing the system down.
Applies to: Windows 10 (22H2) and Windows 11 (23H2, 24H2, 25H2) | Last updated: April 30, 2026
Key Takeaways
- Windows Security (built into Windows 10 and Windows 11) is your primary real-time antivirus and matches paid suites in independent AV-TEST results.
- Layer free on-demand scanners — Norton Power Eraser, AdwCleaner, and Malwarebytes Free — to catch what real-time protection misses.
- Always create a System Restore Point before running any cleanup tool so you can roll back if something legitimate gets quarantined.
- Run Malwarebytes Free weekly and the heavier scanners (Power Eraser, AdwCleaner) once a month as part of routine maintenance.
- Pair this stack with uBlock Origin in your browser and HiBit Uninstaller for trimming startup items — most infections start with a bad ad click or a bundled installer.
Quick Steps
- Search for “Create a restore point” in Start, select your C: drive, and create a new System Restore Point.
- Download and run Norton Power Eraser, then click Scan and remove anything it flags.
- Download AdwCleaner, accept the terms, click Scan, and Quarantine all detections.
- Install Malwarebytes Free, run a full scan, and quarantine anything found. Keep it installed for weekly scans.
- Install uBlock Origin in your browser and use HiBit Uninstaller to clean up unused programs and disable risky startup entries.
In This Guide
This guide covers a layered free antivirus setup for Windows 10 and Windows 11:
- Step 1: Create a System Restore Point — Safety net before any cleanup.
- Step 2: Norton Power Eraser — Aggressive scanner for stubborn malware.
- Step 3: AdwCleaner — Browser hijacker and adware cleanup.
- Step 4: Malwarebytes Free — Weekly on-demand scans.
- Step 5: HiBit Uninstaller + Startup Cleanup — Remove unused software and risky autoruns.
- Step 6: Prevention with uBlock Origin — Block malvertising before it reaches you.
Why You Still Need Antivirus on Windows 10 and 11
An unprotected PC is a liability. Without antivirus, a single drive-by download or malicious browser extension can exfiltrate passwords, encrypt your files for ransom, or join your machine to a botnet without you noticing. From my repair shop years, the most common cause of “my PC is slow” calls was malware silently consuming CPU and bandwidth — not failing hardware.
Windows 10 and Windows 11 ship with Windows Security (also called Microsoft Defender), and it has come a long way. In recent AV-TEST and AV-Comparatives results, Windows Security catches roughly 99-100% of widespread and zero-day malware — the same range as Bitdefender, Kaspersky, and Norton. So the question isn’t whether to install a paid antivirus. It’s whether to layer free on-demand tools on top of Windows Security to catch the edge cases.
The Problem with Paid Antivirus Suites
Paid suites like Norton 360, McAfee Total Protection, and Avast Premium typically cost $40-$100 per year. They duplicate what Windows Security already does, and most of them ship with browser extensions, “PC tune-up” pop-ups, and VPN trial nags that hurt performance more than the malware they’re protecting against.
If you bought a new PC and it came with a McAfee or Norton trial, that’s bloatware — not protection. Uninstall it, let Windows Security take over, and follow the steps below. For a deep cleanup of preinstalled junk, see my guide to removing McAfee or the broader Winhance debloat tool, which I built specifically for this.
Step 1: Create a System Restore Point
Before running any of the cleanup tools below, create a System Restore Point. If a scanner quarantines a legitimate file or breaks a driver, you can roll Windows back to a working state in minutes.
- Press the Windows key and type Create a restore point, then press Enter.
- In the System Properties window, select your C: drive and click Configure.
- Set Turn on system protection if it’s off, allocate at least 5% of disk space, and click OK.
- Back on the System Protection tab, click Create and name the restore point something like “Before antivirus cleanup”.
Step 2: Run Norton Power Eraser
Norton Power Eraser is a free standalone scanner from Norton that’s designed for the stubborn stuff Windows Security misses — rootkits, fake system tools, and malware that hides itself as a legitimate Windows process. It’s portable (no installation needed), so download the latest copy each time you run it.
Open the executable, click Scan, and let it run. When it finishes, review the list — Power Eraser is aggressive and occasionally flags legitimate but unusual files, so check anything you don’t recognise before hitting Fix Now. A reboot is usually required to finish the cleanup.
Step 3: Clean Adware with AdwCleaner
AdwCleaner is a free Malwarebytes-owned tool that targets adware, browser hijackers, search-bar redirects, and potentially unwanted programs (PUPs). It’s the tool I always reached for in the repair shop when a customer’s browser kept opening Yahoo Search or showing pop-ups in random websites.
Download AdwCleaner, run it, accept the EULA, and click Scan Now. When it finishes, click Quarantine to remove every detection — adware rarely produces false positives, so you can trust its results. AdwCleaner usually requires a reboot to finalise the removal.
Step 4: Install Malwarebytes Free
Malwarebytes is the only tool in this stack that I recommend installing permanently. The 14-day Premium trial expires automatically and reverts to the Free version, which is on-demand only — no real-time scanning, no automatic startup, no nags.
After installing, open Malwarebytes, click Settings > General, and turn off “Start Malwarebytes at Windows startup” so it doesn’t compete with Windows Security for resources. Then run a full scan and Quarantine anything detected. Reboot when prompted.
Tip: Run Malwarebytes once a week as a routine. Real-time protection from Windows Security catches active threats; the weekly Malwarebytes scan is your safety net for anything dormant.
Step 5: HiBit Uninstaller and Startup Cleanup
HiBit Uninstaller isn’t an antivirus tool, but it cleans up the conditions that let malware persist. Two specific HiBit features matter here:
- Browser Extension Manager — Lists every extension across Chrome, Edge, Firefox, and Brave. Uninstall any extension you don’t recognise; rogue extensions are one of the top vectors for adware and credential theft.
- Startup Manager — Lists every program that runs at boot, with a VirusTotal score for each entry. Disable anything you don’t recognise — fewer startup programs means a faster boot and a smaller attack surface.
If you’d rather handle startup items, scheduled tasks, and bloatware in one tool with a UI built for it, my own Winhance utility does this with a single toggle and includes Defender exclusion management, telemetry blocking, and bloatware removal in the same window.
Step 6: Prevent Infections with uBlock Origin
Most infections start with a click — a malvertised banner, a fake download button, a “your PC is infected” pop-up. uBlock Origin is a free open-source content blocker that stops the majority of malicious ads and tracking scripts before they ever load.
Install uBlock Origin from the Chrome Web Store, Firefox Add-ons, or the Edge Add-ons store. The default filter lists are enough for most users — no configuration needed. If you’re on Chrome and uBlock Origin Lite is the only option (Manifest V3 limitation), it still blocks the worst malvertising. For full filtering, switch to Firefox or Brave.
Warning: When installing software, watch the installer dialogs carefully. A lot of free programs bundle search-bar hijackers, “free” antivirus trials, or driver updaters in pre-checked boxes. Uncheck everything you didn’t ask for and decline custom installs you don’t recognise.
Recommended Maintenance Schedule
- Daily: Windows Security real-time protection (always on, no action needed).
- Weekly: Run a full Malwarebytes Free scan.
- Monthly: Run Norton Power Eraser, AdwCleaner, and HiBit Uninstaller’s startup audit.
- Always: Keep Windows Updates current. Most malware exploits patched vulnerabilities, so an updated system is the cheapest defence.
If you’re already infected and need to clean things up before this stack will work properly, follow my dedicated malware removal guide first, then come back to this routine. For deeper system cleanup (temp files, unused apps, page file bloat), see how to clean your C: drive.
Frequently Asked Questions
Is Windows Security enough on its own for Windows 11?
For most users, yes. Windows Security in Windows 11 24H2 and 25H2 scores at the top of independent antivirus tests. Layering Malwarebytes Free for weekly scans and uBlock Origin for browser protection covers the gaps without the cost or performance hit of a paid suite.
Will running multiple antivirus tools cause conflicts?
Only if more than one runs real-time scanning at the same time. Windows Security is the only tool in this stack with real-time protection. Norton Power Eraser, AdwCleaner, and Malwarebytes Free are all on-demand only, so they won’t conflict.
Are paid antivirus programs better than free ones?
Detection rates between paid and free products are essentially identical in 2026 — they all use similar engines and shared threat intelligence. Paid suites add features like password managers, VPNs, and identity monitoring, but you can get all of those separately for free or cheaper.
What should I do if a scan finds something serious?
Quarantine the threat, reboot, and re-scan with a different tool to confirm. If multiple scanners flag the same file, delete it from quarantine permanently. If your PC behaves strangely after removal (no internet, missing icons, login loops), use the System Restore Point you created at the start.
Do I need this stack on a brand new PC?
Yes — most prebuilt PCs ship with bloatware, trial antivirus suites, and OEM “helper” apps that are themselves a security risk. Run Norton Power Eraser and AdwCleaner once on first boot, uninstall the trial antivirus, and let Windows Security take over.
