SOLVED: Core Isolation Memory Integrity Incompatible Drivers WDCSAM64_PREWIN8.SYS

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: 1.2.0.0

Published 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.

Categories: Windows 11 & Windows 10Windows Server

138 Comments

Alienated1 · May 14, 2025 at 1:11 pm

I suffered through the wdcsam64_prewin8.sys curse for more than a year but this seems to have fixed the problem. Bless you.

Ian Matthews · May 15, 2025 at 7:09 pm

Awesome Hank!

Jones · March 16, 2025 at 3:44 am

I have the same problem. After I install the latest WD driver, the issue is resolved.

Jenna Lee · April 24, 2025 at 9:09 am

This also worked for me, but my Windows 11 Pro wouldn’t acknowledge an update for the wdcsam64.sys driver. I received a message the driver already had the most recent update, but it didn’t.

Although I purchased the external drive two years ago (WD 4TB My Passport Portable External Hard Drive) it has a 2011 release date. The only way for me to get an update was to install software tools from Western Digital’s website.

The fix for me in order:

1. Installed both WD Discovery and WD Drive Utilities (extract the files before installing.)
2. Using the WD Drive Utilities, I ran two scans: “Run Drive Status Check” and “Run Quick Drive Test.” 3. Received a Pass on both tests.
4. Performed a system restart and the issue is resolved.
5. Checked Windows Core Isolation and its on.

For me, these downloads repaired the issue without having to go through deleting drivers and root files.

Using the WD Drive Utilities without installing WD Discovery probably fixes the issue on its own; but I installed both anyway. I wasn’t sure which download would do what so I’m ok with both installations.

I hope what worked for me works for others.

Daniel N. · May 5, 2025 at 8:57 am

This. This was my exact issue after Win 11 24H2 update. My WD driver was from 2011 and Windows said it was the most recent. I followed these exact instructions and my problem was resolved. My WD driver was updated to a 2020 version by one of these apps, probably the WD Discovery app. After restarting, no issues. Thank you Jenna for such a well described problem with a great (and accurate!) set of instructions! Take care!

Jarmo · February 18, 2025 at 12:39 pm

Hello.
i don’t have wdcsam in the list.
And i don’t see any errors…..or HOW i should see, what driver is broken `?
Can someone do screenshot about how this error looks like from the “pnputil /enum-drivers” list ?
Anyway memory integrity is off, and can’t turn on.

Melanie · December 18, 2024 at 11:00 am

Core isolation was already on for me. To resolve, I uninstalled the driver from device manager, installed WD security and it resolved it for me. Thank you for this post, was the most helpful I found for this issue!

Mike · December 6, 2024 at 1:52 pm

I tried the directory shortcut and received “Failed to delete driver package: The filename, directory name, or volume label syntax is incorrect.”

Matt Daly · November 17, 2024 at 6:03 pm

Bam, just like that, fixed. Super cool, thank you.

Bob · September 28, 2024 at 12:13 am

Thank you for this post. This is still a fairly common problem, but your post is the only solution that actually works – even the Microsoft knowledge base was useless on this issue.

Ian Matthews · October 2, 2024 at 6:10 pm

Thanks for the kind words Bob… we try 🙂

Adam · October 21, 2024 at 10:01 am

JFYI, here’s the complete driver info:

Published Name: oem0.inf
Original Name: wdcsam.inf
Provider Name: Western Digital Technologies
Class Name: WDC_SAM
Class GUID: {8496e87e-c0a1-4102-9d8d-bd9a9b8b07a9}
Driver Version: 01/19/2011 1.0.9.0
Signer Name: Microsoft Windows Hardware Compatibility Publisher

Published Name: oem6.inf
Original Name: wdcsam.inf
Provider Name: Western Digital Technologies
Class Name: WDC_SAM
Class GUID: {8496e87e-c0a1-4102-9d8d-bd9a9b8b07a9}
Driver Version: 07/06/2020 4.55.25.661
Signer Name: Microsoft Windows Hardware Compatibility Publisher

adam · October 21, 2024 at 10:02 am

So…which driver should I delete?

adam · October 21, 2024 at 10:03 am

Which driver do you suggest deleting (one is for my C:\ drive, one is for an external USB drive that I still use)? Will I still be able to use the external drive?

adam · October 23, 2024 at 5:25 pm

This problem cleared up after installing the wd discovery app

Adam · October 19, 2024 at 12:55 pm

I have two wdsam.inf drivers, oem0.inf and oem6.inf. I have an internal Western Digital drive and and external one. Any hints about which driver needs to be deleted?

gerard loyez · August 22, 2024 at 12:00 am

bonjour, soucis idem resolu parfaitement… merci

hello, problems ditto solved perfectly… Thank you

Rupesh · October 17, 2023 at 1:14 am

Thanks, the above step worked. I had the issue with oem65.inf for Sennheiser Communications.

Harvey Ray Fields · October 13, 2023 at 4:39 am

I used this method and it worked to get rid of the file. My issue is, I still can’t turn on the Memory integrity, due driver incompatibilities. I have restarted my computer and still same issue. When I look to resolve any incompatibilities there are no drivers listed.

Jon · January 14, 2024 at 12:24 pm

I have the same issue, where you able to resolve it?

Ólafur Gíslason · September 5, 2023 at 8:33 am

same result – “one or more devices using the same specified INF”. Without oem-number : “the specified file is not installed oem inf.”

Rando · August 24, 2023 at 1:36 am

I also had the same issue where it was telling me that I could not delete the driver. But if you put a space, then type /force it will delete the driver without issue. Just copy this command and replace the with your specific INF number. pnputil /delete-driver oem.inf

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)

Craig · August 21, 2023 at 2:32 pm

Did you run “As administrator”?

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?

Published by Ian Matthews on November 8, 2021