Originally Posted by BetterRed
You have two folders - with the same "book-id" - 1419. One with a longish name and one with a shorter name. Why would that be?
I'm guessing when he switched to the library blank folders were created where calibre didn't see what it expected. So the dupe folders are accessible but don't have the books in them, placeholders if you will.
He needs to go back to the original plalform. Find the books in calibre with long titles and shorten them. Then move the library to Windows 8 at which point he can go ahead and change the titles back to what they were before.