PxHlpa64.sys preventing core isolation

I previously looked at that date and could not find anything because nothing matched with the time of the day. Today, I looked again and, with file explorer. I searched by "datemodified:07/03/2021" (date format has to be adjusted to your system date format). Again nothing matches with the time of the day. I imagine that's a leftover after I uninstalled the culprit. Enough time spent on that, I give up !

Thanks

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It's hard to give up ... I went a bit farther and found that the cdrom.inf was seen as corrupted. I found it was from an epson scanner. I cannot find the original cdrom.inf. Where could I get the original windows 11 cdrom.inf ? I'm quite confident I could fix this Q/"$/?W$/%?" driver problem.

I finally didn't need to reinstall cdrom.inf .... In looking to reinstall the cdrom.inf driver I saw that the current cdrom driver path was referenced to an epson twain scanner driver !!!! I removed this reference, renamed the PxHlpa64.sys OxHloa64.sys.old and deleted the DVD upper filter in registry. Device manager was showing a yellow triangle. After many restarts, DVD came alive !

Now, why windows explorer search for cdrom.inf found nothing ??? I looked at the previous post paths and they contain the cdrom.inf ... Options to show hidden files and protected system files are properly set.

If I open Q-Dir and do CTRL F, it opens a windows explorer window and it finds all cdrom.inf occurrences but explorer by itself is blind when searching in C: drive ! If I navigate to c:\windows\inf explorer finds the cdrom.inf.

Edit : I think I found out ... in the index windows is excluded. I remembered having problem with really slow indexes and I limited the index. As the index problem is solved I just fixed the indexing options.

Thanks to everybody ! J Guy

It has happened to me twice when I installed Adobe CS6. So how do I fix it?

First thing, you certainly have to get rid of Adobe CS6 and then pray to have Adobe removing the old driver when uninstalling it. Then check if you can enable core isolation. If you are not able to enable it, check which driver is not compatible.

jgveill said:

First thing, you certainly have to get rid of Adobe CS6 and then pray to have Adobe removing the old driver when uninstalling it. Then check if you can enable core isolation. If you are not able to enable it, check which driver is not compatible.

The reason for me having this PC is to run CS6

Then forget about core isolation or ... get a newer Adobe version compatible with newer Windows Versions

Oh... so thanks a lot Microsoft. You have screwed CS6 by creating an incompatible driver. It's no wonder people stick with older versions of Windows. I'd love another option or opinion.

Here’s what I did:

Go to C:\Windows\System32\drivers, rename PxHlpa64.sys to PxHlpa64.sys.old

Go to Registry Editor, find HKEY_LOCAL_MACHINE > System > CurrentControlSet > Control > Class

Find 4D36E965-E325-11CE-BFC1-08002BE10318
Delete LowerFilters and/or UpperFilters (I only had LowerFilters)

If you want to play safe, backup this registry key first.

More details on this procedure here:
How to Delete the UpperFilters and LowerFilters Values (lifewire.com)

Restart.

Turn on Memory Integrity and restart.

Now my DVD burner works.
(If you just rename PxHlpa64.sys you can turn on Memory Integrity but CD/DVD will not work.)