A reader wants to know why Windows Defender won’t turn on.

“Some years ago I settled in on having Windows Defender and Malwarebytes Premium as my two programs to keep me out of trouble. With one of the recent releases (2004 or 20H2) Windows 10 turned off Windows Defender and left me with Malwarebytes Premium. When I looked at System Security it told me Malwarebytes was on and everything was OK. For a while I didn’t even notice Windows Defender was turned off. Should I try to turn Windows Defender back on? I could find no way to do that from the System / Updates & Security area. Have you any advice? I would imagine there were a fair number of users using the same pair of programs that I was. I still am surprised I didn’t get some kind of notification when that happened. (Or…I could have simply missed it.)”

Fortunately, this should be an easy fix.

It sounds like Malware Bytes Premium took over as your primary security system and shut off Windows Defender. 

Try these steps:

Open Malwarebytes and choose Settings.

Then, click on the Security tab.

Under Windows Security Center, slide the toggle switch next to Always register Malwarebytes in the Windows Security Center to the off position.

That should take care of it.