I have repeated installed printer and automatic duplex printing works just fine, excepts it flips ONLY on short side even when flip long is checked. It is connected on USB001 Port, RAW Date Format; with print processor hpzpplhn; Driver Name HP Deskjet 9800 Printer Type 3 - User More Driver Version 6.0.6000.55555. One time the Window Printer Test Page listed 20 Add'l Print Driver Files and after another install there were 22 Files. Printer is connected directly to Dell XPS, not through hub.
No matter what is checked, shown in image, or ... it only duplex prints flip short side.
I followed your instructions exactly and the RESULTS worked! Bravo Betty0610. In my Windows search on computer for HP Printer nothing was there. In downloads I had HPPSdr.exe File PsDR-5.5.2.006-HPPSdr which I removed. Later after printui.exe /s under Drivers I had two choices Remove driver only or Remove driver and driver package (hphpabijvst4wu.inf(x64). I removed driver only. Later at c:/programdata I had only HP folder with three items (PDSMQ, SoftPaq, Temp) which I removed.
After that I downloaded and installed software as directed with all the setup items. When I printed off the Windows Printer Test Page I got EXACTLY the same sheet with 22 Additional Print Driver Files as yesterday. I thought "Hmmm" and printed a two page document automatically set for Duplex Long-Side Printing. To my amazement and JOY it printed properly!!!! Oh Joy. This 80 year old Texan who barely recalls Fortran and Cobol was able to follow your directions.
Kudos and Peace. Stay safe in this Covid-19 world.
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