Have you checked the setting on the Sony Device Driver under Preferences->Plugins->Device Interface plugins. You need to make sure that epub is enabled there.
And just to check the obvious - I assume you have epub files to send?
Another thought - if you have epub files and they are DRM encumbered I am not sure if that restricts which Sony devices the files can be sent to? At the very least I would expect them to have to be registered to the same account.
|