Open Source Document Management System | OpenKM

We have over 20k of files in a particular folder, when i click open the folder, below error shows: any guide on where to start checking?

Bad practice, I suggest not have more than 1000-2000 documents into a folder for performance reasons. Anyway you can enable pagination from profiles ( take a look at the tab named "general" in the profiles )

I have turn on the paginate, another folder is having more files than the problematic folder and it doesn't have that error shows. Noted on the performance issues but that shouldn't be error occur right?

It is necessary to take a look in the log ( looking for some error ). About how many nodes are we talking about? You can make a query to the table OKM_NODE where NBS_PARENT column link to the UUID of the parent -> execute a SELECT count(*) to know about what total amount are talking about.

about 8410 documents in that folder and i have view thru all the logs file and unable to pin point the error message and in fact it seems not logged down, any clue? thank you..

Might be is a timeout, I suggest debug your production environment:
https://docs.openkm.com/kcenter/view/ok ... mcatserver

Follow the code in PaginationServlet.java