Question from Ray: I know that Microsoft Defender disables itself if it detects a second antivirus is running but that it’s supposed to automatically turn back on if you remove the other antivirus program.
Well I recently uninstalled McAfee expecting Windows Defender to turn back on, but it didn’t. I keep getting a message saying my computer is unprotected.
Why is this happening and how can I fix it? I don’t like using my computer while it’s not being protected from viruses.
Rick’s answer: You’re right to be concerned about using an unprotected PC, Ray.
Regardless of how careful we might be, viruses and other forms of malware can still find their way onto our machines in various ways.
What I think is going here is McAfee left behind enough remnants of itself to trick Microsoft Defender into believing it’s still installed. And as long as Defender believes there’s another antivirus running on the machine it’ll refuse to turn itself back on.
If this is indeed the case you should be able to quickly get the issue resolved by removing the leftover remnants of McAfee from your system.
Luckily, the McAfee website provides a handy tool for removing all their leftovers. You’ll find it on this page.
Just visit that page and find the “How to remove McAfee software from your Windows PC” section and click the + (plus sign) beside Method #2.
Now click the link to download the McAfee Consumer Product Removal tool (MCPR), then run it once the download is complete.
After the removal tool has finished its job there should be no remnants of McAfee antivirus left on your PC, after which Microsoft Defender should automatically re-enable itself.
Give that a try and let me know how it goes.
Update from Ray: That worked, Rick. Microsoft Defender is enabled and it’s running a scan as we speak. Thanks for your help.