Recently, I have implemented a new feature, via a plugin, on my wiki, so I can read my notes for CompTIA A+ certification offline. After getting the feature enabled, I exported a bunch of pages and tried to open the file in Adobe Digital Editions. However, things did not work out too well.
Why were you looking to get notes offline? Could you not have just accessed them anywhere? Servers are basically software running on top of OSes. Operating Systems need hardware to run on, so servers are generally computers, just like consumer PCs are. The biggest difference is that a server requires a network connection, such as the Internet, if it were a publicly accessible server. Even though HTML5, which as far as I know, is still a draft recommendation, not a full recommendation, allows offline access to web applications, the version of MediaWiki, the software that powers MediaWiki, according to this book, that I use is coded in XHTML 1.x. This means that it does not have the advantages of (X)HTML5. Even using (X)HTML5, the offline access will not work, if the server is down due to network, hardware, or software problems. In addition, reading on paper is still much easier than on a phone, eReader, computer, or tablet. Those devices may get easier to read on as time goes by, but the fact is that paper copies do not need to be protected from data loss by backups. With paper being available all the time, at least until those that believe in man-made Global Warming or Climate Change ban it, one can read from it anywhere they please. Servers, like all other computers fail.
Adobe Digital Editions is supposed to be able to read EPUBs. How can you say that it does not in the title of this post? Finally, we get into the topic of this post. I too assumed that the software would read any EPUB file, but I was wrong. I opened the EPUB that was exported from my wiki and scrolled through it, in order to check its contents, but Adobe Digital Editions crashed with the error message found above. When I looked into it, the EPUB did not validate against epubcheck. This seemed to suggest that there was a problem with the EPUB, but I did not care as getting the articles through wget would have been a pain. When I tried Calibre, in order to see if the file was bad, it worked flawlessly. The only other time I had this problem was with Stanza Desktop, which does not support invalid EPUBs. Yet, another suggestion towards the fact that Digital Editions itself not supporting all EPUB files.
Have you found a solution? No, I have not found a solution to this problem. Easy way is to edit the EPUB until it does validate against epubcheck, but the problem mainly rests with the Mediawiki extension not putting out valid XHTML.
Hopefully, either Adobe Digital Editions will get fixed or the ePubExport Mediawiki extension is updated to have valid XHTML output.
What are your opinions on the matter? Feel free to leave a comment.