They are in the default Windows directory used by the Rack2FIler software. There are seven "bookshelves" about half full of "binders".
I have been exporting important PDF files to insert into Evernote notes, but the volume is too great to do it all manually. I am concerned that Fujitsu might stop supporting, but they have been great so far, I never used the Evernote special IX500, just the "stock" Fujitsu version. Do not what to go thru the legacy then reinstall, I am on version 10.10.5 for windows. I run the local app at home but sometimes use the web or mobile interfaces from the road