When I had that happen to me I read somewhere (here at MR) that it was probably because the file was too big. I think an ePub actually is like an archive of files, and there is a size limit to how big each file can be for Sony to read it.
I'm sure someone who actually knows what they are talking about will come along shortly and give a better answer, but I just wanted to come here and say that it's probably NOT you doing anything wrong.
|