When I download an ebook from my local library using ADE it won't download it into my ADE library only into my computer (the book doesn't appear in my ADE libarary).

...only onto my computer (the book doesn't appear in my ADE library). I am not new to this, I have been using library ebooks for a year now. I am registered, etc, I get now alert/error messages. The ebooks just do not show up in the library so that I can then transfer to my Nook. Can someone please help me?