OK! Found the answer.. Here is the post in case some of you faced the same issue I had..
https://wordpress.org/support/topic/linking-to-a-pdf-file-stored-in-a-sub-folder?replies=12
The lowercase file renaming really did the job and now they can open in page and not directly download.
This is marked as resolved!
Kiranov
UPDATE! It only shows the tag fields of the final step!
Hope that help, and thanks in advance
Kiranov
Hi both,
If you have access to the server/control panel please turn your show error/debugging option off. “You may need to ask your hosting provider to turn it off for you in some cases”
Or it might be turned on in your wp-config.php search for the word DEBUG and set it to false instead of true
Regards and hope that helps
Kiranov