Why is Microsoft Security Essentials still running on my Windows 10?

[deow]

I upgraded from Windows 7 to Windows 10 on a couple of machines. On one machine, everything went well, and Windows Defender replaced the Microsoft Security Essentials that was installed. But on the other, Windows Defender reports at boot that it can't run, and MSE is running instead.

I tried to uninstall MSE, but of course the installer declines to perform any action at all. So how do I get rid of it so I can run the official Windows Defender?

 

[viveknayyar007]

Hello deow

If there is any stubborn program that refuses to uninstall, you can use any free third-party uninstaller that enforces the uninstallation process.

Two mostly used programs are IOit Uninstaller and Comodo Programs Manager. Nonetheless, you can use any uninstaller of your choice.

Hope this helps. Good Luck!!

 

[deow]

Thanks for the response. I used IOit Uninstaller to remove MSE. For the record, Comodo does not as yet support Windows 10, so it declined to install.

Windows Defender still won't run, so I threw on AVG free so I'd have something working while I assess the situation. I think that there are still some small things wrong, but I can live with it for now.

 

[Peter Vintner]

This is what worked for me.
Go to the Services tab on the Task Manager. Find the Windows Defender service and disable it.
Restart the computer. Then check that MS Security Essentials appears in the "All Apps" list with a proper icon rather than a generic one.
MS Security Essentials should now uninstall in the normal way, without problem.
Restart the computer.
Windows Defender should not be working automatically. Go to "settings", "Update & Security", click on "Use Windows Defender" and update it.
If Windows Defender is working automatically, go to the Services tab of the Task Manager and enable it. Then restart the computer and update Windows Defender.

The reason for this procedure (disabling the Windows Defender service) seems to me to be that because Windows Defender prevents the installation of Security Essentials, it therefore prevents its un-installation.