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: 11/29/2017Driver version: 1.2.0.0Published name: oem26.inf
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:
- RIGHT click on the START button and select WINDOWS TERMINAL (ADMIN)
- If you are on Windows 10, select POWERSHELL (ADMIN)
- 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
- Uninstall the driver using pnputil /delete-driver oem<XX>.inf
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.



113 Comments
Guillaume · July 22, 2023 at 9:06 am
I had the same message as Don when trying to remove driver oem47.inf in Windows 11 (Western Digital MyBook)
Don · July 18, 2023 at 12:23 pm
I tried the above solution but got the following message: Failed to delete driver package: One or more devices are presently installed using the specified INF. Suggestions?