You may not be able to open files or run or install apps due to false positives from “Virus and Threat Protection”, the security software Defender that comes standard with Windows 11. In this case, pausing Defender will allow it to operate. Pause Defender only when you are certain that the app, file, etc. is virus-free. This page introduces how to temporarily stop Windows 11 Defender.
See the separate page below for instructions on how to completely disable Defender’s antivirus.
Disable/enable Windows 11 Defender
Open Defender Antivirus settings
To disable/enable Windows 11 Defender, use “Windows Security” under “Privacy and Security” in the Settings app. 1. Click the “Start” button and click “Settings” in the Start. 2. Click “Privacy and Security”, and when the setting screen appears, click “Windows Security”.
3. Click Virus & threat protection.
4. When the Virus & threat protection screen appears, click Manage settings .
In the displayed “Virus & threat protection settings”, set the antivirus operation.
Toggle Defender Stop/Start
Stop virus and threat protection
Click the real-time protection switch button and click Yes when User Account Control appears.
If the switch button is “off”, it is in a stopped state.
After Defender stops, you’ll see “Your real-time protection is off and your device is in a vulnerable state.”
Starting virus and threat protection
Click the real-time protection switch button to turn it “on” and it will start.