The Vox is a general table rather than a dedicated eReader, and needs the appropriate software installed.
See thread http://forums.adobe.com/message/4775728 for more details.
In summary, for library books, install the Overdrive app. That avoids the need for ADE/PC at all if you so wish.
For general ADE compatibility, install the Aldiko app.
Pointers to both on the page http://goodereader.com/blog/electronic-readers/essential-kobo-vox-apps-and-tools/