I cannot print pdf - files for my business after I upgraded to Sonoma 14

Why not? Are you getting some kind of error message? If so, what does it say? A screenshot might be helpful.

Sometimes this can be caused by 3rd party printer software. It could be the driver for your printer, or it could be some 3rd party software that tries to take over all PDF handling.

Try restarting in Safe Mode as described here: Start up your Mac in safe mode - Apple Support

I have had trouble with our (2013!) Canon MX922 not printing *some* items correctly—eg, our Calendar month view, under Sonoma. The same missing lines and fade-out text, even when printed to a PDF and printed from Preview. Other docs, print fine.

So I brought my Canon iB4120 printer, a more recent model, home from my office. It works fine. Also, our iPad & iPhones always print *similar* iOS docs fine.

Related to this, with no printer at my office, I added an office-mate's shared printer to my laptop—a quite old Canon C5045 that I installed as a “generic PostScript” device. It handles that same Calendar page (and my other work stuff) like a champ

Meanwhile: Canon tech support says they do not supply the printer drivers and Apple's support pages show a “driverless” approach since approximately Lion. The “CanonPrinterDrivers.DMG” file referenced in an Apple support page updated Nov/2023, has a 2008 .PKG that Sonoma refuses to load as from an unidentified developer.

The problem seems much more general than “Apple no longer supports PostScript.” Something else is up

macOS Sonoma has dropped support for PostScript. Some programs generate PDFs using this. These files will no longer render properly and thus not print.