I touch problems

My I Touch is recognized on my computer under ITunes and I can transfer new audio/music files to it from ITunes. BUT I no longer can transfer an audiobook from Overdrive Media Console. It does not recognize my ITouch when it is plugged in and says that "no portable devices could be found". The connection of the ITouch to the computer is intact. I have downloaded the latest Overdrive. Is my ITouch too old and broken?