replied on January 25, 2023
Just a guess here.
Since it sounds like it only happens with certain PDFs from certain sources, I wonder if it is possible that the PDFs are set-up as InDesign version of PDF instead of Acrobat version? Indesign adds a lot of extra functionality to PDFs, but it could be screwing with how Laserfiche processes them. I haven't encountered this myself within Laserfiche, but I have with multiple other applications, where they just couldn't do processes that they can do with other PDF documents. If you open the PDF in Acrobat or Reader, go to File > Properties > Description > Application, it might indicate if the application is set-up for InDesign. Also, as you work with the PDF, if the fields on the PDF ever re-arrange or make major changes like adding pages, it's a good bet that it is set-up for InDesign.
If this is the case, you might want to try to run the document in Laserfiche without page generation and using Acrobat or Reader as the viewer instead of the Laserfiche Viewer.
Again, this is just a guess, as I haven't personally seen this behavior within Laserfiche, but have with some other software.
Good luck! I hope you find a solution!