I found a weird problem in one of my articles (now unfortunately corrected!) whereby a PDF filename which both on the server and in my local master copy on my PC had spaces within, and these files were “not found” both with a browser going to the website and with a browser opening the locally stored index.html.
I two 2 or 3 different versions of Dreamweaver for knocking up my simple linear websites and wonder if perhaps there is a setting in the index.html headers which affects the way a browser (FF in this case) would deal with those files.
In the index.html file, the said filenames had the spaces replaced with %20 which is what normally happens when you create a link to such a file using Dreamweaver. I still have plenty of such files in my articles and currently they do work.
Normally I avoid filenames with spaces…