If they are in different directories then it will be fine - in fact this is good from a W3C standpoint as the top-level discovery page would be simply the directory, and not the "specific technology that is used" - i.e. you can go to ht tp://yoursite.com/update/ instead of ht tp://yoursite.com/update/index.html. So I am sure that Google wouldn't care much. However - if you are talking about in the same directory... ummm... well.... what he ^^ said
Yea, uploading another index.html will upload the old one... but I'm not sure if on some operating systems having the filename different with regard to case is possible. For example, can you have index.html, Index.html, and INDEX.HTML side-by-side on a linux server? The server I use at HostGator is running linux and its filesystem is case-sensitive, but my system is extremely slow and I don't want to be the one to test it right now. :/ If Google didn't have a problem with the case, then I think your only concern would be duplicate content. Perhaps you're talking about dynamic parameters, ie yoursite.com?cat=1 and yoursite.com?cat=2 ? AFAIK you'd only have to worry about duplicate content.
so u mean multiple like having one at || domain.com/index.html having one at || damain.com/sub/index.html etc etc? If so that is how most sites are run (however the index page is not always page index.html, but its property is the same as index.html)
So multiple index.html files on my server is OK? I have also been told that this violates the unique filename/url Google guideline? This is my problem: http://www.mydomain.co.uk/subdomain/index.html but is only seen as http://www.mydomain.co.uk/subdomain/
surely index.htm is different from index.html so they cannot be overwritten even if in the same directory