I Can't Uninstall Microsoft Security Essentials (Windows 10)

Here is the solution to those having problems with Microsoft Security Essentials not being removed prior to Windows 10 upgrade and then being left with it still running after the upgrade.

Open File Explorer

Browse to C:\Program Files\Microsoft Security Client\

Locate the file Setup.exe, right click on it and choose properties

Click on the Compatibility tab

At the bottom of the tab click 'Change Settings for all users'

On the next screen check the box for 'Run this program in compatibility mode for:' and choose Windows 7

Click OK

Click OK

From the taskbar search box type cmd.exe and right click and choose 'Run As Administrator'

This will open an elevated command prompt as Administrator

In the command prompt window copy/paste or type the following:

C:\Program Files\Microsoft Security Client\setup.exe /x /disableoslimit

Choose to Uninstall

Once this has finished reboot and Microsoft Security Essentials will be gone and Windows Defender should be running correctly.

>>> HERE IS THE FIX <<<

I had the same problem, followed some advise in the forums...didn't work for me.  I tried my own combination of things and it worked, very simple. 

Follow exactly as I describe, not sure if it will work through other window menus...which I mean the compatibility tab may not show.  Just follow instructions below.

First, you must change the compatibility user settings...for some reason its set for Windows 8.

A) In Windows 10, click on "Start"

B) Click on "Files Explorer"

C) Left click on your "Local Disk - System C" drive

D) Double left click on "Program Files"

E) Double left click on "Microsoft Security Essentials"

F) Right click on MSE "Setup.exe"

G) Left click on "Compatibility" Tab

H) Check off the "Compatibility Mode box" and select "Windows 7"

I) Left click "Apply"

J) Left click on "Change settings for all users"

K) Again...Check of the "Compatibility mode" box and select "Windows 7"

L) Left click on "Apply" and Left click on "OK"

M) Left click on "Ok" again.

...Then proceed to Uninstall instructions below.

A)  In Windows 10, click on "Start"

B) Click on "All Apps"

C) Click on the "Windows System folder"

D) Click on the "Control Panel"

E) Click on "Programs"

F) Click on "Programs and Features"

G) Left click on "Microsoft Security Essentials"

H) Right click on "Uninstall/Change"

...when finished uninstalling, reboot computer. 

Windows Defender will automatically be protecting your pc.

That's it...It worked for me.

Good luck...I hope it works for you.

Here is the solution to those having problems with Microsoft Security Essentials not being removed prior to Windows 10 upgrade and then being left with it still running after the upgrade.

Open File Explorer

Browse to C:\Program Files\Microsoft Security Client\

Locate the file Setup.exe, right click on it and choose properties

Click on the Compatibility tab

At the bottom of the tab click 'Change Settings for all users'

On the next screen check the box for 'Run this program in compatibility mode for:' and choose Windows 7

Click OK

Click OK

From the taskbar search box type cmd.exe and right click and choose 'Run As Administrator'

This will open an elevated command prompt as Administrator

In the command prompt window copy/paste or type the following:

C:\Program Files\Microsoft Security Client\setup.exe /x /disableoslimit

Choose to Uninstall

Once this has finished reboot and Microsoft Security Essentials will be gone and Windows Defender should be running correctly.

Thank you for the fix!

One thing I had to change was had to add inverted commas to your command:

"C:\Program Files\Microsoft Security Client\setup.exe" /x /disableoslimit

and it worked.

Hope that helps anyone else having this issue.

I still suggest to roll back  to Win 7, then uninstall MSE and then to do the upgrade to Win 10 again.

See also Community Moderator  https://answers.microsoft.com/en-us/profile/7364dc73-c954-4722-a16c-fba6b21015bfStephen Boots ' reply in another thread:

Cheers,

J

If Security Essentials is still installed and running on the machine post Windows 10 Upgrade - please execute the following command from an elevated command prompt (Search > cmd.exe > (Right-Click) > 'Run as Administrator')

MsiExec.exe /X{75812722-F85F-4E5B-BEAF-3B7DA97A40D5}

A dialog box will prompt you to continue.

This will start the uninstall and automatically enable Windows Defender.

From <http://answers.microsoft.com/en-us/protect/forum/protect\_defender-protect\_start/windows-defender-only-partially-enabled/6b03889f-a14f-476e-8df2-337e6e94be06?page=2>

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If that doesn't work I suggest to roll back  to Win 7, then uninstall MSE and then to do the upgrade to Win 10 again.

Also see reply of Stephen Boots in another thread:

Cheers,

J