replied on December 1, 2023
A "trailer" is a particular part of a pdf document that is important to be able to find to read it correctly. In general, Laserfiche doesn't inspect the documents you attempt to import - since we allow all types of files, it's not really possible in general. But for certain types of files, we support operations like page extraction. If you have an option like that checked during the import, we need to be able to successfully read the document.
It is likely that there is something not quite right with that particular pdf. Other applications may not have a problem with it, but it may trip up the page generation library. PDF is a complicated format, and it's not uncommon to see different behaviors like that, or for many applications to be able to handle technically incorrect documents.
Turning off page generation may get you past this step, but if you require pages I think you'll need to open a support case so we can take a look at the document.