Windows Defender can be disabled in settings. (can also be enabled again after so dw)
Windows 10:
Select the Start button, then select Settings > Update & Security.
Select Windows Defender, then turn Real-time protection on or off.
Windows 7:
Press the Windows + Q key on the keyboard to bring up the charms search.
Type “Windows Defender” in the search box and then press enter.
Click Settings and make sure there is a checkmark on Turn on real-time protection recommend.