Windows 11 · Windows
Turn On Microsoft Defender Real-Time Protection
Source-checked About 10 minutes
Answer
Open Windows Security > Virus & threat protection > Manage settings, then turn on Real-time protection. Another antivirus or policy may control the setting.
Confirm the current security provider
Open Windows Security > Settings > Manage providers and check which antivirus product is active. Microsoft Defender can enter a reduced or passive state when another compatible antivirus is installed, so an unavailable toggle is not automatically a Windows defect.
Open the documented Defender control
Select Virus & threat protection > Manage settings. Under Virus & threat protection settings, turn on Real-time protection. Do not leave protection off while downloading files; Microsoft notes that files opened or downloaded are not scanned while it is disabled.
Install pending security updates
Open Settings > Windows Update, check for updates, install current security intelligence and Windows updates, then restart. Return to Windows Security and test the toggle again rather than assuming the first display state persisted.
Check for organization management
Look for wording such as This setting is managed by your administrator and check Settings > Accounts > Access work or school. On a work, school, or family-managed PC, contact the administrator instead of altering Group Policy or registry values.
Remove only an unwanted third-party conflict
If a third-party antivirus is listed and you intentionally no longer use it, uninstall it through Settings > Apps using the vendor's supported process, restart, and confirm Microsoft Defender becomes active. Do not delete program folders or security registry entries manually.
Verify protection rather than only the switch
Return to Virus & threat protection and confirm Real-time protection is on and security intelligence is current. Run a Quick scan if protection had been unavailable, then review Protection history for unresolved actions.
Video walkthrough
If it does not work
- If Windows Security is blank, reports a service error, or still shows administrator management on a personal PC, capture the exact wording and use Microsoft support. The removed legacy registry-deletion method is intentionally omitted because it can override policy, weaken protection, or damage managed configuration.
Sources and verification
Checked against official documentation on . Scope: Windows.
Follow the linked first-party guidance if labels differ after a platform or app update.