I have start getting this message when trying to open books borrowed from the library. I have been borrowing from the library for years and this message is new. I am doing nothing different and it happens for books newly checked out (not all thank goodness, but some). I can open the book on my computer in Adobe Digital Editions, and I can click on my Nook (in Adobe Digital Editions) and the book opens fine.
But when I unplug the Nook from my computer (whether I use the Eject function or not, I have tried both) and try to open the book I get this error.