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  • Core Isolation – Driver Incompatibilty

    Home » Forums » AskWoody support » Windows » Windows 10 » Windows 10 version 21H1 – May 2021 Update » Core Isolation – Driver Incompatibilty


    Greetings –  I had actually originated this thread as part of a TPM question I had.  Although somewhat related, I think it best to start from scratch.  My system consists of an MSI Z390-A board, an Intel i5-9600k processor, and 16 Gb of Corsair DDR4 RAM, running WIN 10, version 21H1 with the October updates installed.  The default setting for this board is TPM disabled.  I had been running the system that way since I first put it together in January 2020.  Preparing for an eventual WIN 11 upgrade, I went ahead and activated the TPM module, which I think went without a hitch.  Continuing with trying to establish more security features, I tried to activate the core isolation selection/memory integrity feature in settings.  It was unable to activate because of two driver conflicts.  I deleted them both: one deletion was fine, but the other turned out to be one of two CD ROM drivers.  One driver is CDROM.sys, and the other is PxHlpa64.sys.  The latter is from Corel Corp, which perhaps got installed when I installed WINDVD Pro 11 awhile back.  Apparently both of these drivers are necessary for the optical drive to work.  I was hoping to get by with just CDROM.sys, but the drive does not work without both.   Device Mgr shows amber and a Code 39 message.  After restoring my system, I tried to work around things by temporarily putting a dot old at the end of the file name.  I then activated Core Isolation, followed by removing the dot old extension.  Windows didn’t like that and subsequently turned off the Memory Integrity feature by itself.  If the PxH… driver came with the installation of WIN DVD Pro, I doubt there’s nothing newer.  I’ve worked considerably with the folks at Corel on this software for other issues, so everything in it is as current as will likely to be.  I look to be up the proverbial creek.   The date on the PxH file is 9/13/13.  Hopefully there’s a fix here.  As always, the help is appreciated.

    Casey H.

    Viewing 3 reply threads
    • #2398426

      Is WINDVD Pro 11 the latest version of the WINDVD software (is there a WINDVD Pro 12 or later)?
      Have you checked for the latest firmware/software for the CD ROM?

      1 user thanked author for this post.
      • #2398525

        I think there is a later version, but it would be a new purchase.  I actually have WINDVD Pro 12, not 11 as I incorrectly wrote.  I also have service pack 8 installed, which is the most recent service pack.  I had also updated the firmware on the optical drive–went from 1.03 to 1.05.


    • #2398428

      CDROM.sys should be sufficient to use the drive. Try removing the PxH driver. Then remove the CD-Rom drive and re-boot. Windows should discover the hardware and use the correct driver.


      1 user thanked author for this post.
      • #2398526

        I think I did that (by renaming the driver file), but I’ll try again, as I may not have the sequence correct.


      • #2398542

        I tried again with the same results.  Removing the driver (file name change to dot old), then removing the device, then rebooting leads to:

        Windows cannot load the device driver for this hardware.  The driver may be corrupted or missing. (Code 39).  Object name not found.  I also uninstalled WINDVD 12 Pro.  That did not remove the PxH driver.  I’m not sure that this software is even the problem.  I suspect so, because the driver manufacturer is Corel, and I don’t think I have any other Corel product on the machine.  Reinstallation of WINDVD has left me back at Service Pack 7.  The Service pack 8 upgrade file doesn’t work.  Very frustrating.  Renaming the file back to normal and rebooting returns the drive back to normal.  That still leaves me with a file that won’t allow me to activate the memory protection feature.  I don’t want to reinstall Windows from scratch–too big of a pain.  I’m thinking I can get along without the memory protection feature.



    • #2398431

      If you’re not using the optical drive for playing DVD/BluRay discs purchased at retail, you probably don’t need WinDVD.

      As Joe suggested, do the following:

      1) Uninstall WinDVD (Add/Remove Programs)
      2) In Device Manager, right-click the DVD/CD-ROM drive and select “Uninstall device”
      3) Reboot the computer

      Go back into Device Manager to verify Windows has installed a generic driver for the optical drive.

      As a side note, I just checked and WinDVD is up to version 12 which supports H.265 playback. Upgrade pricing is available.

      WinDVD Pro 12 – Ver Comparison

      I don’t know whether the drivers in the new version work with VBS enabled.

      If you’re going to upgrade the computer to Win 11, you needn’t be concerned with “Memory integrity” (VBS) – it will be optional. Most non-business upgraders will likely not enable this feature due to the performance impact.

      1 user thanked author for this post.
      • #2398436

        If you’re going to upgrade the computer to Win 11, you needn’t be concerned with “Memory integrity” (VBS) – it will be optional.

        I don’t know much about this, but:

        In most cases memory integrity is on by default in Windows 11, and can be turned on for Windows 10.

        Core isolation — Memory integrity []

        Windows 10 Pro version 21H2 build 19044.1387 + Microsoft 365 (group ASAP)

      • #2398527

        Sorry–I do have 12, not 11.  And I have a number of DVDs and Blu Ray disks that I have purchased.  I have tried the VLC Blu-ray workaround without success.  Leawo works for BR, but not for some of my DVD collection.  I originally got WINDVD because it was on sale for 25% off.  In retrospect, I’m wishing I had gone with Power DVD.


    • #2398441

      Here’s my understanding of VBS thus far:

      1) If upgrading to Windows 11 from 10, the default setting of 10 (off) will be retained.

      2) If doing a clean install, VBS will be enabled.

      3) If purchasing a new Win 11 computer (OEM), then VBS will be enabled by default.

      There have been a number of reports that VBS impacts FPS in some games.

      Microsoft’s Virtualization Based Security feature can slow performance

      In my own testing on an AMD 5800X (anecdotal), the custom power plan I was using was affected. Also, I observed a small, but measurable, reduction in effective core clock boost speed.

      2 users thanked author for this post.
      JohnW, b
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