Windows · Privacy & Security
Manage Windows Security & Antivirus
Windows Security is the built-in protection center for virus & threat protection, firewall & network protection, and device health. It runs Microsoft Defender Antivirus and lets you review recent scans and threats.
How to open Windows Security
- Open Settings → Privacy & Security → Windows Security.
- Select 'Virus & threat protection' to run a scan.
- Review 'Firewall & network protection' for your active network profile.
- Check 'Device performance & health' for an overall status summary.
What you should know
- Run quick, full, or custom antivirus scans on demand.
- Review the firewall and network protection status for each network profile.
- Check app & browser control settings that guard against phishing and malicious downloads.
- View device performance and health reports.
If you install a third-party antivirus, Windows Security automatically steps back for real-time protection — you can still use it to review overall device health.
Why it matters
Windows Security is your first line of defense against malware, ransomware, and network intrusions, and it's already running for free whether you notice it or not. Understanding what it's telling you means you can catch a real threat early instead of dismissing a warning you don't recognize.
Best practices
- Run a quick scan at least once a week, and a full scan monthly or after downloading files from unfamiliar sources.
- Keep 'Tamper Protection' turned on so malware can't quietly disable your antivirus.
- Review the firewall's active network profile whenever you connect to a new network, especially public Wi-Fi.
- Don't install a second full antivirus suite alongside Windows Security — running two real-time scanners at once causes conflicts and slowdowns.
Common problems and fixes
- Windows Security shows a red or yellow warning icon.
- Open the app and check which section is flagged (virus protection, firewall, or account) — it usually names the exact problem and offers a one-click fix.
- A trusted file keeps getting quarantined.
- Add it as an exclusion under 'Virus & threat protection settings' → 'Exclusions', but only for files and folders you fully trust.
- Real-time protection appears greyed out or won't turn on.
- This usually means a third-party antivirus is installed and active — uninstall it if you no longer want it, then Windows Security will resume automatically.
Tips and tricks
- Pin the Windows Security app to your taskbar so you can check its status without digging through Settings.
- Use 'Core isolation' under Device security for extra protection against firmware-level attacks, if your hardware supports it.
Frequently asked questions
Do I need to buy separate antivirus software?
No — Microsoft Defender Antivirus inside Windows Security provides solid baseline protection for most users at no extra cost. Third-party suites add extra features some people want, but they aren't required.
Will scanning slow down my PC?
A quick scan uses minimal resources and usually finishes in a few minutes. Full scans are more intensive, so it's best to run them when you're not actively working.
Does Windows Security protect against phishing links?
Yes, partly — SmartScreen (under App & browser control) warns you about known malicious sites and downloads, though it's not a substitute for being cautious with email links.
Related settings
- Camera PermissionCamera Permission controls which applications are allowed to access your device's camera. Managing these permissions helps protect your privacy and ensures that only trusted applications can capture video or images.
- Microphone PermissionMicrophone Permission lets you control which applications can use your device's microphone. This is essential for maintaining privacy and preventing unauthorized audio recording by untrusted software.
- Network ResetNetwork Reset restores all networking components to their factory default settings. This includes removing all saved WiFi networks, resetting TCP/IP stack, and clearing DNS cache. Use this as a troubleshooting step when other network fixes have not resolved your issue.
More Privacy & Security guides for Windows
- Privacy & SecurityPrivacy & Security is the central hub introduced in Windows 11 that groups Windows Security (antivirus and firewall), sign-in options, app permissions, and general privacy controls like diagnostic data and activity history into one settings category. It's the starting point for auditing everything related to your PC's security and data posture in one place.
- App PermissionsApp Permissions organizes privacy controls by capability rather than by app, letting you see at a glance which installed apps can access location, contacts, calendar, file system, and a dozen other data types. Instead of checking each app individually, you pick a permission type and review every app that has requested it.
- BitLocker Device EncryptionDevice Encryption (built on BitLocker technology) encrypts your entire system drive so its contents are unreadable to anyone without your Windows sign-in credentials or a separate recovery key, even if the physical drive is removed and connected to another PC. It's automatically available on many modern PCs that meet specific hardware requirements, and can be extended to additional drives on Pro, Enterprise, and Education editions.
- Location PrivacyManages whether Windows and individual apps can access your device's location, including the master location toggle and per-app permissions for location data.
- Diagnostics & FeedbackControls how much diagnostic and usage data your device sends to Microsoft, along with feedback frequency, tailored experiences, and options to view or delete diagnostic data.
- Activity HistoryControls whether Windows stores a history of your app and browsing activity locally and, if signed in, syncs it to Microsoft to power features like Timeline-style continuity across devices.