I am trying to download a book from the public library. I downloaded and activated Adobe digital editions. when i download the book from the library site - it appears in my ADE but I can't figure out how to get it to my nook. the nook does NOT show up as a bookshelf in the ADE.

I dragged the book from the ade to the nook directory through windows so now the book shows up in the nook "my documents" folder but when I try to open it I get this message: "Sorry, unable to open this book." or sometimes I get a "User not activated" message. I have checked the help sections for adobe digital editions but have not been able to figure this out. any help would be appreciated.