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8 Ways to Fix Windows Defender Not Working/ Opening [Tested]
Remove interfering apps & files, reset Defender & more
6 min. read
Updated onAugust 21, 2024
updated onAugust 21, 2024
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When Windows Defender isn’t working, it’s most likely due to system file problems, or because you have or have had athird-party antivirusinstalled on your PC. Also, Windows Defender may not open if the Security Center is disabled.
No matter the specific issue, the solutions below should help you sort it out.
How do I fix Windows Defender not working?
1. Check your system files
TheSystem File Checkerrepairs corruption in system files. You can use it to verify whether Windows Defender is corrupted or not.
If youcan’t run an SFC scanor if SFC can’t fix the problem, you might want to try using a DISM scan instead. To do that, just follow the next step.
2. Clean boot your computer
Sometimes third-party applications can interfere with Windows and cause this problem to appear. However, you can find the problematic application by performing a Clean boot.
3. Remove third-party antivirus tools
If you have another antivirus installed on your PC, it can interfere with Windows Defender. To make it work, uninstall said antivirus. Then make sure it’s completely gone by following the steps below:
Uninstall the remnants of your previous antivirus, restart your computer and Windows Defender should be automatically enabled.
⇒Get IObit Uninstaller
4. Restart the Security Center Service
1. PressWindows key+ Rto launch theRun app.
2.Typeservices.mscin the Run dialog box and hitEnteror clickOK.
3.In Services, search forSecurity Center.
4.Right-click on it and selectRestart.
- Once you restart the required services, check if the problem with Windows Defender is resolved.
In order for Windows Defender to work properly, you need to have certain services enabled. If those services aren’t running properly, Windows Defender won’t be able to turn on at all.
However, you can always start the necessary services by performing the steps above.
5. Change your group policy
Sometimes Windows Defender won’t turn on because it’s disabled by your group policy. After making these changes, it should work.
6. Modify your registry
If you’re an advanced user and you prefer using the command line, you can do this fromCommand PromptorPowerShellby performing the previous steps.
Some users are also suggesting deleting theDisableAntiSpyware DWORDkey, so you might want to try that as well.
7. Restart Windows Defender
8. Install a better antivirus
Windows Defender is a decent security solution for your PC, but it can’t match the services and features of a third-party antivirus.
If you’re using the Internet for shopping, banking, work, and communication, you must protect your sensitive data with a top antivirus like the one recommended below.
This tool supports all major platforms, including Windows and Android, and provides advanced banking and privacy solutions.
Over 110 million users trust ESET’s multilayered protection solution in the world so make sure you try it. You can benefit from a 30-day trial period right now.
ESET HOME Security Essential
Wrapping up
With that, we conclude our guide. We hope that our solutions helped you fix this Windows Defender not opening problem for good.
We also have a guide that explains what to do if youcannot open Windows Defender Scans folder, so don’t miss it.
If you’re an advanced user, you can useCMD virus scan commandto get rid of the malware.
For any other suggestions on how to deal with this problem, write us a comment below.
More about the topics:Windows Defender issues
Madalina Dinita
Networking & Security Specialist
Madalina has been a Windows fan ever since she got her hands on her first Windows XP computer.
She is interested in all things technology, especially emerging technologies – AI and DNA computing in particular.
Prior to joining the WindowsReport team, she worked in the corporate world for a number of years.
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Madalina Dinita
Networking & Security Specialist
Madalina is a Windows fan since forever, especially interested in AI, emerging technologies, privacy, and security.
