You need to make sure it is registered with the same Adobe ID that you used on the previous computer (and on the Nook).
Sometimes ADE gets its registration/activation confused and in a semi-authorized state..
Try completely removing any authorization using ctrl-shift-D to ADE (cmd-shift-D if on Mac).
Restart ADE, and then reauthorize with your Adobe ID.
If the info on the nook doesn't match the reload of the ADE on my laptop, how do I change what is on the nook?