It seems that Nook are closing their UK operations and we're being moved over to Sainsburys Entertainment instead.
One of the requirements of the transfer is that we have to download and install Adobe Digital Editions on the computer (Windows 7 Pro) then use it to 'Authorise' both the computer and the Nook, in order to download books first to the computer and then transfer to the Nook.
I did all this and it worked perfectly well. I got an Adobe ID, ran and installed ADE, authorised the computer and then authorised my Nook. I bought a book, downloaded and transferred it to my Nook. All good - everything worked as it should.
Next, I got an Adobe ID for my wife because she has a Nook as well. Remember that ADE is already on the computer and the computer is already authorised, so now I connect her Nook to authorise it with her Adobe ID. ADE sees that there's an unauthorised Nook attached but the only ID it has to authorise it with is mine, not hers, and it won't allow me to input her ID anywhere.
Of course, this isn't going to work because we both have separate Nook (and now, Sainsburys) accounts with different books in them and different credit/debit cards paying for them, so she obviously needs to have her own Nook authorised with her own ID - doesn't she?
So, what do we do?