System extension message warning

It is a utility you installed, perhaps long ago, related to that printer. If I had to guess, considering it's HP, it is some ink or toner monitoring process that lets you know those supplies are running low. Those things never had to be installed to begin with since they amount to annoying nags that benefit only the printer manufacturer by selling you overpriced ink — a significant source of revenue for them.

To uninstall it, you will need to research your printer's documentation. In other words, consult HP.

You wrote that you deleted all HP programs. Be advised one of them may have been the one you needed to uninstall that system modification, in which case you might have to install it all over again for the sole purpose of uninstalling it in accordance with that documentation.

You can also choose to ignore it. If and when you upgrade macOS to a version yet to be released, that Intel code will not even load and the nag will cease. The file(s) invoking them will remain present but inert, vestiges of a bygone era.

If you don't know where to begin and want the easy way out, download and run EtreCheck, which (among many other features) provides a report of system modifications likely to be responsible. Post its report in accordance with the following instructions: How to run the Etrecheck Diagnostic Tool - Apple Community

EtreCheck does not require an installation procedure, so it requires no complimentary uninstallation procedure. When you are finished using EtreCheck you can simply drag its app icon to the Trash... unlike HP's junk software.

Etrecheck was run and lists 19 'not-loaded' extensions, most with HP names, (also Epson, canon, Seagate, jmicron, CDSDAudioCaptureSupport) all dated 2013 or before, and located in Macintosh HD/Library/Extensions. I suppose I can attempt to delete, my current printer/scan is the HP8600 using air-print and epson scanners to macstudio and all work without these extensions, and the rest do not exist anymore. OS27.0.1 when deleting intel apps and related files almost always completely deleted, never allowed moving to trash which is ok, but have wonder about mistakes not being allowed.

I think you have answered my question, advise please of anything more I should be aware. Thank you.

Posting the EtreCheck report might help others identify the responsible process or processes so that you might eliminate the nag, but if everything else is working to your satisfaction I'd consider leaving well enough alone.

There are at least two factors to consider: launchable apps (programs) developed exclusively for Intel CPUs (non-"Universal"), and processes invoked by system extensions that are not directly launchable. It's the latter category you are encountering. In some cases they can be difficult to identify, or difficult to remove once identified, while others are easily removed. In any event they will cease to function in the next major macOS release.

That's the reason I tend to err on the side of doing nothing. The dialog itself is merely informative, and a (probably futile) attempt on Apple's part to avoid the inevitable complaints that ensue with every macOS upgrade: "Apple broke <fill in the blank> by forcing this upgrade on me!!!"

A warning is triggered when you launch an Intel-only app, and you will see it every time you launch such an app. Launching a recently used Intel app again won't trigger it, but if enough time has passed then you'll see the warning again for that app. For example, I last used the SynologyAssistant app to check on my NAS over a month ago, and launching it generated the banner message.

To avoid this issue you need to run only Universal or Apple Silicon apps. For apps that are Intel only, contact the developers and push them to release updated versions of their apps (but keep in mind that they have over a year before their apps stop working on macOS). 

To see which of your apps are Intel and thus need to be updated or they won't run on macOS 28 (Fall 2027), hold the Option key and click the Apple menu, then select System Information (the top item). Select Applications in the Software section of the sidebar, then click on the Kind column header to sort them. 

Some apps aren't readily identifiable by the name, but when you select that app you will get more info. For example, 'commandFilter' is a component of the Epson printer drivers. If you no longer use them, then apps like that can be safely deleted. The location to the application/extension can be seen in the report, to navigate to the app in Finder simply select and copy the above path up to and including the last / (but not the app name itself) then in Finder select Go menu > Go to Folder, paste the path and press return. As an example, the path to be pasted from the example above is: 

/Library/Printers/EPSON/Fax/Filter/

Here's what Apple has to say about updating your apps:

Learn how to update Intel-based apps for Apple silicon - Apple Support

To neuroanatomist ---- What you are explaining is not my situation. When booting after a shutdown, after putting in my password, as the desktop appears, a warning message appears as attached. I have no hp apps that are intel, all are universal. And at the MacHD /Lib/extensions level are 19 extensions with 13 having hp in the name (others w/o the hp) and none are loaded and all date from year 2013 back to year 2005 and the hp printer works off air-print without these extensions. Opening Sys set lists the 13 hp named extensions with the all set to no and I have the option to make yes. Since OS-27 was loaded I get this dialog. I had also had a similar message for Epson, but after deleting the old intel print app, that stopped. Sys settings does not list any intel hp print apps. I still have two apps built for intel, whose alternatives are web based and need to shift later. So the question becomes what is the trigger for the hp extension denial?

Interesting, thanks for the clarification. Unfortunately, I have not run across this issue previously.