Simple ways to turn off Windows Defender in W10.
1. Type Defender in search, turn off in Defender panel under settings.
2. Open All Settings, Update and Security, Windows Defender.
Microsoft probably would not like WD turned off on Builds that we are supposed to be testing..
Just for the record, reg tweaks to disable WD, even when disabled, it still runs.
Additionally, you can also delete the WD folder, just to be sure, takes ~500MB.
I just did this, Can I get in there and shut off the service now, too? Ah, it's shut off now, but I wanna get rid of the little defender icon. Defender is the one thing left over from earlier versions of Windows I totally despise, although I did use it in Windows 8 for the longest time.
Google and Download "Taskill.exe"
You might find it here:
Taskill Download - Softpedia
Make a folder such as C:\Taskill and put taskill.exe into it. Make a desktop/taskbar shortcut to it. Open up properties of shortcut and in the field that says "Target" type in the box: C:\Taskill\taskill.exe MSASCui.exe
Now if you have the notification icon option turned on for Windows Defender when you run the Taskill shortcut you should see it go away. Waiting to see if it turns itself back on but so far it hasn't. If anything, the shortcut to kill the process definitely makes things easier to deal with.
Hope that helps
But I did find a way to really permanently disable WD.
Boot up eg. Win 7 installation
Press Shift + F10 to open CMD
Go to your system drive (eg. C: )
Open up the Program Files folder (cd "Program Files")
Rename Windows Defender folder to something else (rename "Windows Defender" somethingelse)
Create a new file called Windows Defender (eg. echo something > "Windows Defender")
Reboot and remove installation media.
Windows can't find or run Windows Defender because the folder and the nasty .exe files inside are no longer where they're supposed to be. It also can't restore or reinstall Windows Defender since there's already a file or folder called Windows Defender.
Do not open Windows Defender in Settings. Settings will crash.
Opening Windows Defender in Control Panel gives out an error.
To restore WD, just delete the file you created, rename somethingelse to Windows Defender and reboot your PC.