With Windows 10 1803, I decided to switch on Memory Integrity Isolation into Core Isolation options of Windows Defender Security Center.

The problem is that once activated, the switch is disabled, and it is not possible to switch it off.

Naturally, I have found, that this feature has some problems about:

• some of the old drivers may not work properly
• Virtualbox doesn’t work

These forced me, to seek a way to turn it off.

After a short investigation, I found this page with a very good tutorial:

https://www.tenforums.com/tutorials/104025-turn-off-core-isolation-memory-integrity-windows-10-a.html

Then I found some more information about:

https://docs.microsoft.com/en-us/windows-hardware/customize/desktop/unattend/microsoft-windows-deviceguard-unattend-hypervisorenforcedcodeintegrity

The Solution

You can switch it on and off this feature by opening the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\DeviceGuard\Scenarios\HypervisorEnforcedCodeIntegrity

and then updating the following DWORD value:

Enabled (0 = disabled, 1 = enabled)

A reboot is needed to apply to the value.

PS: it is possible to download .reg files to update this value from the tutorial page (the first link).