I usually download ebooks from the public library, and have never had a problem accessing them on ADE. Today I actually purchased a book from B&N, and I am getting this error message when I try to add it to my ADE library: "Document is licensed for a different user account." Any suggestions?
I think B&N use the Adobe authorization mechanism, but their own IDs.
This may be one (rare) case where ADE 2.0 is better than v1.7.2, as I believe it can cope with multiple IDs; one Adobe one and also separate vendor IDs.
Which ADE version are you running?