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Windows defender won't turn on

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3 replies to this topic

#1 sdaly1


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Posted 01 April 2015 - 10:08 PM

So today my McAfee trial expired, using the removal tool I uninstalled it before attempting to switch on windows defender.

A few problems have occurred, I click on the windows defender icon and the "windows defender has been switched off" message appears. I go to the action centre and the system 32 folder appears.

I try the command prompt method to enable windows defender and it also does not work

I try running a scan via command prompt and it tells me some corrupt files have been found

I have also tried changing the start up setting from manual to automatic but I cannot seem to do this as the option is greyed out

Is malware causing the prevention of windows defender being switched on? Bearing in mind my computer has recently had a reboot and also works at top speed.

Please help

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#2 noknojon


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Posted 02 April 2015 - 12:55 AM

Start with Windows Defender - Turn On or Off in Windows 8 these details from Brink in the Windows 8 Forum area..
Once you have read and followed the details, please post back with any concerns ......
Thank You -

#3 justinkemp99


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Posted 02 April 2015 - 04:28 AM

Go to the Control Panel Click on administrator, select the use this program check box and then click save. Then click on the action center icon in the taskbar and turn on the virus protection links

#4 quietman7


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Posted 02 April 2015 - 05:39 AM

If a third-party trial anti-virus came preinstalled on your computer or you installed one yourself, it most likely turned Windows 8 Defender off (disabled) to avoid conflicts since it includes anti-virus protection. Windows 8 Defender will remain disabled until that anti-virus software has been completely uninstalled and then Windows 8 Defender needs to be activated if you choose to use it. When uninstalling the third-party anti-virus you may receive a message indicated your system has no protection...click here to turn on Windows Defender. If not, you will need to manually turn it on.

noknojon provided a how to link. Here is another.Also check to make sure the Windows Defender 8 service is running (enabled).

To start (enable) a service, press the WINKEY + R keys on the keyboard or click the Start Orb > Run...,
and in the Open dialog box, type: services.msc
Click OK or press Enter.

Note: You can also click the Start Orb and in the Search Box, type: services.msc

Windows Services will open:
  • Click the Extended tab at the bottom to view all the info on your services.
  • In the Services applet, scroll down the list and find the Windows Defender service.
  • Double-click on the name of the service to open the Properties page.
  • In the Properties Window > General Tab that opens, click the "Start" button if it is stopped.
  • From the drop-down menu next to "Startup Type", click on "Automatic".
  • Click "Apply", then "OK" and close any open windows.

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