I see others have had this problem but nothing was resolved. I have an old Sony and a new Kobo and cannot load books onto either of them. I put away the Sony when I bought the Kobo last spring and have had no problems at all until I bought some books at the beginning of this month. Several error codes later I have just the one CE_COPY_NOT_ALLOWED and when I click on the book itself get "The document is licensed for a different user account" I have uninstalled and reinstalled ADE twice and still get the error. (I cannot put the books onto the Sony either). I unauthorized the computer and tried using an older account, which I thought was defunct but worked, and still get the error. I tried unauthorizing the computer, same result.
I tried using the chat forum but the person there has no clue and told me to come here, because there are "experts" here.. Obviously many others have had this problem without any help. I really hope that there is someone out there who knows how to fix this problem; otherwise I have paid for hundreds of books that I cannot read (Kobo told me to reset my reader) as well as much $$ for the new reader itself.
And now I am getting yet another error. Since I unauthorized the computer, I went back to authorize it again and now get this error, in RED.
"You can only authorize this computer with an Adobe ID that hasn't been previously used to authorize any other computer or mobile devices. Please try again.
I only have one computer. I will however, be getting a new laptop in the near future and would need to put ADE onto it. Apparently now I cannot.