Cannot turn on Memory Integrity

wdcsam64_prewin8.sys is an incompatible driver, and Memory integrity will stay off until that driver is updated or removed.

Try this end-to-end path:

1. In Windows Security go to Device security > Core isolation details > Memory integrity.
   • Confirm the blocked driver shown is wdcsam64_prewin8.sys.
2. Update or remove the driver.
   • Microsoft guidance is to check with the device manufacturer for an updated compatible driver.
   • If no compatible driver is available, remove the device or app that installed that driver.
3. If the driver still appears after uninstalling the related app, remove the driver package from the driver store.
   • Open Windows Terminal (Admin).
   • List third-party drivers:

          dism /online /get-drivers /format:table
     

   • Find the published name for the related driver package, such as oem13.inf.
   • Remove it:

          pnputil /delete-driver oem13.inf /uninstall /force
     

   • Restart the PC.
4. Try turning Memory integrity on again.
   • Path: Windows Security > Device security > Core isolation details > Memory integrity.
5. If Memory integrity still will not enable, check whether Windows blocked the driver load.
   • Open Event Viewer.
   • Go to: Applications and Service Logs\Microsoft\Windows\CodeIntegrity\Operational
   • Memory integrity compatibility events are generally Event ID 3087.
6. Verify whether Memory integrity is actually enabled.
   • Check System Information (msinfo32) under Virtualization-based Security Services Running, or check the Core isolation page again.
7. If the system became unstable after enabling Memory integrity, use recovery only as a last resort.
   • Risk: registry changes can affect boot behavior.
   • In Windows Recovery Environment, the documented command to turn Memory integrity off is:

          reg add "HKLM\SYSTEM\CurrentControlSet\Control\DeviceGuard\Scenarios\HypervisorEnforcedCodeIntegrity" /v "Enabled" /t REG_DWORD /d 0 /f
     

About Windows Update hanging at 0% download: the provided material only supports the Memory integrity and incompatible-driver side of the problem. The supported fix here is to remove or update the incompatible driver first, restart, then retry enabling Memory integrity and retry Windows Update.

References:

• Device Security in the Windows Security App
• Enable virtualization-based protection of code integrity
• Memory integrity and VBS enablement
• incompability with memory integrity - Microsoft Q&A After installing the latest 24H2 update, I received a security warning. It informed me that a device driver was not compatible with Windows memory integrity. I needed to update the driver for the device in question, but there was no better update available. I then removed the device itself, including the driver for that device via Device Manager. However, this did not solve the problem. I can no longer enable memory integrity. When trying to enable it, I am alerted to the incompatibility of that specific driver. But I can update that driver anymore. I removed it.