If you are trying to tighten up your security by adding Virtualization-Based Security (aka VBS) to your Windows 11 you might find this error:

Core Isolation  Memory Integrity
Incompatible Drivers WDCSAM64_PREWIN8.SYS

Driver date: 11/29/2017
Driver version:

Published name: oem26.inf

Windows 11 Core Issolation incompatible driver wdcsam64_prewin8 sys

This is an old driver that ships with both Windows 10 and Windows 11 and very few people need it.  In fact we have never run into a situation of any machine using WDCSAM64_PREWIN8.SYS .

Fortunately, it is very easy to remove:

  1. RIGHT click on the START button and select WINDOWS TERMINAL (ADMIN)
    • If you are on Windows 10, select POWERSHELL (ADMIN)
  2. You can then list all of the drivers on your computer using pnputil /enum-drivers and find the one with WDCSAM64_PREWIN8.SYS or you can just look at the error message.  In my case the driver that needs to go is OEM26.INF
  3. Uninstall the driver using pnputil /delete-driver oem<XX>.inf

2 Windows 11 Core Issolation uninstall - remove incompatible driver wdcsam64_prewin8 sys

You do NOT need a reboot so you can immediately retry to enable CORE ISOLATION and you should see a prompt to reboot once Core Isolation > Memory Integrity is turned ON.

Windows 11 Core Issolation Reboot Required


Christiano · December 5, 2021 at 5:24 am

Many thanks, it’s work to me !

Martin Bligh · November 20, 2021 at 6:45 am

Cannot delete this driver

Questions or Comments?