But What if the defender stops working? Yes, it does happen, and it is mostly caused by glitches in the registry, group policy, or conflicts created by third-party software. The defender not working leaves the PC completely vulnerable to attacks. Do not worry as it can be fixed with some slight changes in the windows settings. We have compiled a list of alternatives to try out. Try them one by one till the defender starts working again.
Common Causes of Windows Defender Not Working
How to Fix Windows Defender Not Working?
The solutions stated below are centered toward windows 10 and 11. Please try one alternative at a time, check if the defender works and if it doesn’t move on to the next alternative. As the exact reason for the defender not working might differ from PC to PC, there is no alternative except trying a hit or miss approach.
Start by Restarting the Device
For any kind of error or problem in windows, the first go-to step is to reboot the device. We know it sounds like a generic solution but often, issues/ errors get fixed with a simple restart. As windows start each process once again, the process that created the error also gets restarted creating a high chance of the error not recurring. If the defender still doesn’t work, move on to the next alternative.
Uninstall Third-Party Antivirus
When we install a third-party antivirus on a computer, it takes over as the resident malware-fighting software. Try uninstalling the antivirus and check windows security once again. Once the antivirus is completely gone from the pc, the defender will automatically take over as the default antivirus. We also recommend using PC Cleaner/Removal Tools, there are many free and paid versions of these types of software. This product cleans any residual files left from the previous antivirus which might conflict with the windows defender. For most users, this will be the key solution to why the defender isn’t working.
Modify Local Group Policy Editor
If the defender is disabled by the group policy editor, it will not work. Follow the steps to check if it’s not the same configurations listed in the steps.
Modify the Registry
Please back up the registry (linking) before making changes to it. Any mistakes in the registry can damage the OS and stop the computer from working.
Run a System Scan & DISM Repair
We recommend doing a DISM restore to repair the window image as well as a system file checker to scan & fix any system files/window image. If the issue is caused by corrupted files or images, the command stated below will help repair it.
Update the Operating System
Please make sure the window OS is updated to its latest version. Windows update ensures the software, drivers, and services run at their latest version. The update might also contain any newly identified bug fixes by Microsoft. Updating the OS gives us one more thing to cross out from possible solutions.
Download and Run Windows Troubleshooter
We can get a download file from the official Microsoft page to run a troubleshooting program for the Windows security issues. This is not the windows troubleshooting that we see on our settings, it’s a separate file that we download from the Microsoft site and run on our PC. It’s mainly made for windows 7,8,10 but does run on windows 11 too. Give it a whack and see if the troubleshooting file helps you out.
Try Resetting Appx Package
These commands are a bit technical but in essence, they list the appx packages in the user profile and reset it and bring it to their original settings. Appx files were first introduced in Windows 8, they contain metadata, files, and credentials needed to install a Windows application To reset the appx packages, follow the steps below:
On Windows 10
On Windows 11
Try a Clean Boot
Some apps or services might conflict with windows defender causing it to not work. We can try a clean boot where we disable all unrequired services and apps from the PC. If the defender works after disabling these things, we can conclude it’s one of the apps or services that is the problem.
Check Window Services
Window services show a list of services that manage long-running processes in the operating system. If these services stop, then the software related to these services will also stop working. So we need to check if services relating to windows security, antivirus, are running.
Run an MRT scan
This is a malware scanning tool made by Microsoft itself. It can identify any malware on the device and clean it out. If the defender issue is caused by malware, this will be an excellent help.
Reset Windows Security
Reset the Whole Device
In the worst-case scenario, if nothing else works, we recommend resetting the device. There steps to windows 10 and 11 are almost the same. The only difference is that the recovery option is found under System (windows 11) instead of windows (10) Update & Security.
Conclusion
If any of the steps above didn’t work, we recommend doing a clean Windows OS installation. It does sound drastic but will most likely be a guaranteed solution. We recommend backing up any important data first in an external device and then proceeding with reinstalling the operating system on the PC.
