Originally Posted by BensonBear
Putting this issue aside, what was the problem with those two files? I looked into the original html trying to find something that those files had and none of the other 220 files had. And indeed there was something: the value of the "name" attribute in various <a> files has colons in them. For references, for example "Carnap:23a" was used as a reference to a paper Carnap published in 1923. This was carried over to Calibre's command line ebook-convert epub files. I don't know if this is allowed in html or epub's xhtml or not, except that every program I tried does accept it: all browsers, all epub readers I have on my pc.
A couple of other comments: even if colons are not allowed (I don't feel too much like checking this out now, but I can't imagine why they are not), it is not because of that that Kobo failed. Otherwise it should just tell is there is a syntax error in the epub file. It should give much better behavior in this case, not a hang or crash.
You may well have struck upon something here. I had a web page from Wikipedia, saved in htm via Word and converted to epub by Calibre that would consistently freeze up the Kobo on page 6. Eventually I deleted everything after page 5, as that was all I really needed, and now the Touch can handle it.
I just went back and checked the original Word file, there are three instances of "Template:" in the offending page. So even though the epub imported into the Touch ok it looks as though the Touch may freeze on rendering colons in tags.
I agree that it's a very inelegant way of handling errors.