I am trying to download ebooks (epub files) from my macbook to my nook e-reader through adobe digital editions but keep getting error messages and cannot to open documents. I have re-installed the digital editions software, double checked that the computer is authorized and that my adobe ID username/password are accurate, but I keep getting the message "user not activated" when trying to open the downloaded epub file on my nook. Of note, documents will open just fine on the macbook in digital editions without any error messages.
addended: once I posted this, it showed links to other forums of similar topic, interesting as when I originally searched nothing showed up under this topic, but nonetheless, found something that worked so hooray:
From what you've said, I'm thinking you haven't registered your Nook with
B&N. During that process, you should use your Adobe ID and password.