Hey there,
Yes, the type and creator code can sometimes be used as a quick fix, but only if the file is indeed a valid (uncorrupted) file.
More important than the type and creator code info is the actual "internal structure" of the file itself. For example, all Adobe Acrobat PDF documents begin (internally) with the line "%PDF". If a file you try to open doesn't begin w/ this, Acrobat will give an error message that the document isn't a PDF document, or at least not a valid one.
In other words, the type and creator code don't guarantee anything about the file's actual format or content.
Also see the following posts for more info:
http://www.gnutellaforums.com/showth...threadid=10840 http://www.gnutellaforums.com/showth...threadid=11120
"Either people are recycling and sharing corrupted files - or...."
That's exactly it. Why the hell people would want to do this, I don't know. Usually if I encounter a corrupt file, I'll keep sharing it, but in all caps add "DAMAGED" to the file name so hopefully people will get the idea before they download. That's better than just deleting it, in my opinion. Also, you can check to make sure you don't download it again.
Yes, I've encountered quite a few corrupt files (I also use Mac OS X) but usually have found a good version. Usually, the larger the archive file's MB for a given app, the better chances you'll have that it might be good. Emphasis on "Usually."
Hope this helps....