turning off defender:

You may disable Windows Defender in the Windows Registry as well. Basically, it is the same setting that gets written to it when you disable the application in the Group Policy Editor.

Tap on the Windows-key to open the Start Menu.
Type regedit.exe and hit enter.
Confirm the UAC prompt to continue.
Navigate to the following key: HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender
If you see the preference DisableAntiSpyware on the right double-click on it and set it to 1 to disable Windows Defender.
If the preference does not exist, right-click on Windows Defender and select New > Dword (32-bit) Value, and name it DisableAntiSpyware.
To restore Windows Defender at a later point in time, delete the key or set its value to 0.