Sometimes ADE gets its registration/activation confused and in a semi-authorized state..
Try completely removing any authorization fri=om ADE using ctrl-shift-D to ADE (cmd-shift-D if on Mac).
Restart ADE, and then reauthorize with your Adobe ID.
It is unlikely that the authorization has got wrong on your Nook, but if that still doesn't wor,
deauthorise the Nook as well (ctrl-shift-E to ADE while Nook plugged in), restart ADE and reauthorize the Nook.
