Server 2016: MMC has detected an error in a snap-in. It is recommended that you shut down and restart MMC

Question

I get the error message stated in the subject line whenever I try to open Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> from GPO.

Checking the event viewer I get the following message:

Faulting application name: mmc.exe, version: 10.0.14393.3750, time stamp: 0x5ed5e019
Faulting module name: wsecedit.dll, version: 10.0.14393.3930, time stamp: 0x5f4f3474
Exception code: 0xc0000005
Fault offset: 0x000000000003ae38
Faulting process id: 0xd80
Faulting application start time: 0x01d6a15073250db8
Faulting application path: C:\Windows\system32\mmc.exe
Faulting module path: C:\Windows\system32\wsecedit.dll
Report Id: bb088e23-0d43-11eb-8448-0894ef325bdc
Faulting package full name:
Faulting package-relative application ID:

The event ID is 1000

Answer 1

This was broken with the September 8, 2020—KB4577015 update. currently the only solution is to uninstall it.

--please don't forget to Accept as answer if the reply is helpful--

Answer 2

This issue affects only the local security policy 'DontDisplayLockedUserId'.
In a case you don't use this specific policy, you can remove it using registry. After MS release a fix, you can import it back.
I've made the command line available below:

reg export "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SecEdit\Reg Values\MACHINE/Software/Microsoft/Windows/CurrentVersion/Policies/System/DontDisplayLockedUserId" C:\Temp\DontDisplayLockedUserId.reg

reg delete "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SecEdit\Reg Values\MACHINE/Software/Microsoft/Windows/CurrentVersion/Policies/System/DontDisplayLockedUserId" /f

The first line will create a backup inside C:\Temp, and the second will remove it.

At the time MS release a fix, you can safely import it back.

Hope it helps, stay safe!