Windows 10: Windows Defender Antivirus won't turn on

I get prompts telling me I need to turn on Windows Defender Antivirus every time I turn on my laptop. When I go to the security center I do not have the option to switch any of the toggles to On, they just remain grey.


Windows 10 came installed on this laptop.


I have not installed, nor can I find, any conflicting anti virus software on here.


Anyone got any ideas what I need to do please?

:)

 

Windows defender is turned off and won`t turn back on

Windows defender on windows 10 enterprise won`t turn on. This happened shortly after i updated it; when I try to turn it on it says:

This app has been turned off and it isn't monitoring your computer.

And right underneath it, it says:

If you are using another app for malicious and unwanted software use Security and Maintenance to check that app`s status.

Need for a response ASAP, thanks

 

Windows defender is turned off and won`t turn back on

Did you just upgrade to Win 10?

I notice you're using Win 10 Enterprise. Are you part of a network and/or connecting to the internet via a server?



The behavior you are describing is typical if there are remnants of a third party program interfering with Windows Defender. This may occur even if WD was working okay on Win 8.1 before you upgraded to Win 10.



https://support.microsoft.com/en-us/help/17187/windows-10-protect-your-pc
Note the comment in this document published by Microsoft that Windows Defender automatically turns off if you install another antivirus app.



Go to Security and Maintenance, look in 'Security' and see what program is listed under Virus Protection. Windows Defender will not be enabled and working properly if there is a program other than Windows Defender
listed.



Think back to what other antivirus programs have been previously installed. Do you remember which AV product came pre-installed or was previously on the computer? Maybe McAfee or Norton? Try running the removal tools for any AV
program that has ever been on the computer and then reboot...then try enabling Windows Defender though it might be automatically enabled and working properly.



See List of
anti-malware product removal tools



Have you tried the steps recommended in Problems
starting Windows Defender in Windows 8/8.1/10 ?



For further information see the reply of quietman7 in
this thread: Windows Defender.



Alternatively you can consider a reset which will essentially be a “clean install” of Win 10 but you’ll lose installed programs and data/pics/music that is on the computer. https://support.microsoft.com/en-us/help/12415/windows-10-recovery-options



Or - install a third party antimalware program (doing so should disable the real time protection of Windows Defender) and use the third party program for your antivirus protection.



Choosing an Anti-Virus Program



Is Windows
Defender The Best For Windows 10? Good article but ignore the ads.



AV Poll 2015 - Security | DSLReports Forums



http://windows.microsoft.com/en-US/windows/antivirus-partners#AVtabs=win10



Good luck...



Top 10 Ways PUPs Sneak Onto Your Computer. And How To Avoid Them.

 

avast free antivirus vs windows defender

>it's true that Avast Free Antivirus is better by a lot compare to windows defender?

As
BulldogXX already mentioned: That's a matter of opinion.

Suggestion to read:

• Choosing an Anti-Virus Program
• Safe Steps for Replacing your Anti-virus - Why should you use Antivirus
  software?
• Supplementing your Anti-Virus Program with Anti-Malware Tools
• Best Practices for Safe Computing - Prevention of Malware Infection
  

Suggestion to watch: