hello there!
i am making a magazine…these days and we are few hours before printing
now i correct the mistakes and i close pdf files again only the pages that had problem…but in some pages i have this warning
one or more of the pages specified are not valid page names
All I can say is, over that time, Adobe has not improved their software, if anything it has devolved. Been doing this 20 years myself and the day something doesn’t go sideways unexpectedly is a day to celebrate.
Good luck.