Had the same problem on my home computer, not on the one at work. On my home box, I had only java 7.21, at work I had java 7.21 and 6.29 (x64). I tested to install the older java version at home, and see, it started up as it should! So apparently, there is some problem with Pocket and late java versions!
I know it's been a while, but has the desktop app been updated to handle Java 7 or higher (my pc shows that I have version 8 installed)? I can't get the app to launch after installing. Not even an error msg appears when trying to launch.