Again I cant prove the point on this machine due to win 10 issue (still checking if its just my pc) however the most basic test for SumatraPDF rather than the Printers Limits is to try sending one image as a page to printer as 2x pages.
Use a simple png or jpeg (not webp or heic) or a small 1 page PDF to avoid any memory issues
the following chunk is not your issue (you get 1 page) but for others may hint what may block 1st attempts at printing
Using 3.4.14215 (older than current 14221)
First message is
Printer does not exist that’s Me error, I used wrong name of the printer
Second intent I use local “shared name” and get error
Printer with given name does not exist, that’s windows insisting, For that network printer to add print server
Third I try “\\servername\Printer Name” and get
Couldn't initialize printer (so I am closer as the print server seems to have responded)
So I pull up that printers preferences and try a test print it reports problems (so that’s the server I am currently suspicious of)
So let me use a different wi-fi network printer, success I can see the one page has been placed in to the printer spool queue, and a few minutes later 2 duplicate sheets of paper come out.
So beware there is no evidence 2x is sent to the printer but the physical printer accepted the 2x command. So for example a 7 page pdf I am printing will show as 7 pages whilst printing 7 to 1 in reverse twice. it finally reports 7/7 for the 14 pages collated in reverse in the output tray. (Note that simple printer does not have a stapler which is a known corporate problem setting e.g. should it have punched 2x7 or 1 x14)
That’s a tree and a half of todays carbon allowance used up.
Just updated that working install to 3.4.14221 just to test it can print with latest pre-release without known problems and that Windows 7 Pro is working well with todays version (only a newer apple ios heic image can not print)