I had recently disabled windows defender on windows 10 and when I did I know want to enable it again but when I open action center and press Turn On Now it does nothing. I have pressed it multiple times and with no result. Fix: press Windows Key + R type regedit locate the following path * HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\WINDOWS DEFENDER* Right Click this file and select permissions press Advanced where it says owner press change change the owner to your username Now press apply then ok select Full Control from the permissions menu (click the Widnows Defender folder ) Find the value DisableAntiSpyware and DisableAntiVirus and set these values to 0 (explaination: double click each and where the 1 is put 0 and press ok) Open services.msc find Windows Defender there should be 2 services: Windows Defender Service and Windows Defnder Netwrok right click each and press start after you have started both restart your computer Run Windows Defend er I Hope this Helps! Feel Free to Reply

Fix: press Windows Key + R type regedit locate the following path * HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\WINDOWS DEFENDER* Right Click this file and select permissions press Advanced where it says owner press change change the owner to your username Now press apply then ok select Full Control from the permissions menu (click the Widnows Defender folder ) Find the value DisableAntiSpyware and DisableAntiVirus and set these values to 0 (explaination: double click each and where the 1 is put 0 and press ok) Open services.msc find Windows Defender there should be 2 services: Windows Defender Service and Windows Defnder Netwrok right click each and press start after you have started both restart your computer Run Windows Defend er I Hope this Helps! Feel Free to Reply

I don't believe it. Microsoft better acknowledge this is there problem. I just updated my second daughters PC that was also running Win 7 Home Premium. Again Windows Defender will not run. No more excuse I did not uninstall Microsoft Security Essentials or left some other malware program installed. I made sure I uninstalled all of them and my younger daughters PC has the same exact problem. Why doesn't Microsoft acknowledge this problem at the very least. How about a fix!

Yeah, it is "solved" alright. I just spent a long time with the chatty lady (forget the name she used) on case #1299471618. The short summary is: Microsoft will NOT allow us to have third-party AV software under Windows 10. If you DO install third-party software, that installation will stop Windows Defender from running (without giving you any warning or reason--it just won't run) and the OS will complain loudly about the fact that it is not running every few minutes, with no way to stop the complaints. I have confirmed on the two lap-tops here that removing F-Prot and Spybot--Search and Destroy will allow Windows Defender to run, doing what ever it does. Where I am between the hammer and the anvil on this machine is that I broke something trying to "fix" the unfixable and it won't run even with the third party stuff removed. I have an call appointment to see if that can be fixed. Bah! I don't believe it. Microsoft better acknowledge this is there problem. I just updated my second daughters PC that was also running Win 7 Home Premium. Again Windows Defender will not run. No more excuses. I did uninstall Microsoft Security Essentials and uninstalled any other malware programs that were installed. I made sure I uninstalled all of them and my younger daughters PC has the same exact problem. Why doesn't Microsoft acknowledge this problem at the very least. How about a fix!

I don't know why but I uninstalled Iobit's Advanced System Care and both daughters PC's were able to turn on Windows Defender. Both daughters are running Windows Defender with Malware-bytes and Malware-bytes Anti-Exploit so I guess the ASC was the problem I have ASC on mine and never encountered a problem but I upgraded from Win 8. Maybe that had something to do with it. For the future I guess you have to get rid of all malware, anti-virus and any third party cleaners that offer some type of protection. I still think Microsoft should fix this problem. Thanks.

I turned off Windows Defender to download printer drivers. Turned off my computer so that Defender could reset its self. It is all greyed out and I can't turn it back on. I don't think everyday users should have to go to the system registry to fix a Windows problem!

Windows 10: Windows Defender will not turn on SOLVED

Anonymous

I had recently disabled windows defender on windows 10 and when I did I know want to enable it again but when I open action center and press Turn On Now it does nothing. I have pressed it multiple times and with no result.

Fix:

press Windows Key + R
type regedit
locate the following path *HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\WINDOWS DEFENDER*
Right Click this file and select permissions
press Advanced
where it says owner press change
change the owner to your username
Now press applythen ok
select Full Controlfrom the permissions menu

(click the Widnows Defender folder)

Find the value DisableAntiSpyware and DisableAntiVirus and set these values to 0

(explaination: double click each and where the 1 is put 0 and press ok)

Open services.msc
find Windows Defender
there should be 2 services: Windows Defender Serviceand Windows Defnder Netwrok
right click each and press start
after you have started both restart your computer
Run Windows Defend er

I Hope this Helps!

Feel Free to Reply

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