I downloaded my first library book from overdrive to ADE. I get window "unable to open book"

[Avista1013]

I downloaded my first library book from Overdrive on ADE.  The book shows up on my Nook under my documents.  But, when I go to read it, I get a message, "Sorry, Unable to open the book"

What am I doing wrong?  Thanks.

[Avista1013]

I think I figured it out.  I was dragging from ADE to my Nook's drive.  I just needed to drag to icon on ADE.  Thanks.  Can now read my book.