Joe, just in case you might be able to pick the scab and replicate my "discovery"....

On my 2017 MBP 13" with Touch Bar MacOS 10.14.5, I had lost the ability to print PDF's to my HP LaserJet M1536dnf MFP which had been working fine for years....it would now print the following error message instead of the chosen page:

ERROR: limitcheck
OFFENDING COMMAND: imagemask

STACK:

(r)
(Sys/Start)
(Sys/Start)

This was unveiled when I couldn't print my USAA updated insurance cards....

Before deleting and reinstalling the printer, I tried:

1. sending the PDF to the Preview app prior to sending it to the printer - same result

2. changing the default printer driver from "AirPrint" to the HP M1536 driver - same result

3. printing the offending file from a different computer (and from my iPhone using AirPrint) - SUCCESS! So it wasn't a corrupted PDF.

4. my other multi-function printer, a Brother MFC-985DW worked just fine with printing and scanning using the Print / Scan prefpane....

Upon deleting then reinstalling the HP M1536 printer I discovered that the new printer was no longer recognized as a multi function device, and there was no longer a SCAN option.....very annoying!

So now I went through the driver update process with HP's support site to ensure that I had their latest releases, deleted and reinstalled the printer again and still no scan option....even more annoying!

Looked a little further on the HP support site and discovered a later firmware release for the M1536 MFP, however, there was no MacOS way to get that into the printer....now I'm digging out a legacy Windows computer to run the firmware installer. End result, it will now print the PDF correctly, but still no scan option using my MBP....now I'm starting to get concerned.

Ran the MacOS 10.14.6 update (and supplemental)....still no scan option using the System Preferences Print & Scan prefpane.

Ultimately researched the scanning work-around solution to be:

Use the Image Capture app that Apple now includes since 2018 in the Applications folder.

This new app has the same UI as the previously functional Scan portion of the Printer/Scanner prefpane, so once you find it you are on familiar territory.

Immediate issue resolved....it prints correctly and I can use a different work-flow to scan.

Now, the rest of the story.....

Same OS, same printer, same network, 2014 Mac Mini.....no change to the ability to print PDF's correctly....no error messages, no loss of Scan option using the Printer / Scanner prefpane, no need to use the Image Capture app as a work-around.

Any suggestions for me on kext research/comparison between platforms? FWIW, the HP scanning software that was in their latest release also works just fine (their older scanning software utility was 32 bit...)


Freedom is never free....thank a Service member today.