How to verify Microsoft Defender and SmartScreen are on

Why this matters

Windows ships with strong built-in protections — Microsoft Defender Antivirus and SmartScreen — that block known malware, phishing sites, and dangerous downloads. They’re usually on by default but third-party AV installers, leftover settings, and old tweaks can disable them. A five-minute check confirms you’re getting the protection that’s already there.

Defender on its own is now competitive with paid antivirus products in independent testing (AV-Test, AV-Comparatives). Combined with SmartScreen’s URL and download reputation system, it handles the realistic threats most users face.

How to do it

1. Open Windows Security (search for it in the Start menu).
2. Click Virus & threat protection → Manage settings. Confirm these are On:
   • Real-time protection
   • Cloud-delivered protection
   • Automatic sample submission
   • Tamper protection
3. Go back, click App & browser control → Reputation-based protection settings. Confirm these are On:
   • Check apps and files
   • SmartScreen for Microsoft Edge
   • Phishing protection
   • Potentially unwanted app blocking
   • SmartScreen for Microsoft Store apps
4. If you installed a third-party AV in the past and aren’t using it actively, uninstall it — running two AVs causes conflicts and disables Defender.

What you don’t need

You don’t need to pay for Norton, McAfee, or any third-party antivirus on a personal Windows PC in 2026. Defender + SmartScreen + auto-updates + a password manager cover what consumer AV bundles add.