I am not a computer geek. I run Windows 7. I had been successfully using ADE 3.0, but it stopped working. I installed ADE 4.0. Now, when I try to download a library ebook, I get this lovely error message: E_AUTH_BAD_DEVICE_KEY_OR_PKCS12. I've seen other people asking about this, and I've tried the things recommended, but nothing is working. Must I give up my Nook???? I even tried to install the Calibre program someone recommended, but I can't get my fool laptop to recognize it. Grr.
If anyone can help me, I would be most grateful. Reading is the best thing in my life, and I love my Nook. I'm going insane!