'Help' and 'Authorise Computer' both the old account and my new email address (account)
Have you had two different accounts, or did you change the email address associated with your one and only account?
When ADE2 shows your registration information it shows something like:
emailuser@gmail.com | AdobeID (urn:uuid:ff2ddc22-eca0-46c6-a84d-123456789abc)
The internal ID is created when the account is set up and is permamently associated with the account.
Books are associate with the account using that internal ID.
Once accessed on a given account, the book can never be read on another account.
However, it is possible to change the email address associated with an account
(log in at the Abobe website and go to your account information).
If a book is not associated with the account/ID that ADE shows, you won't be able to open the book.
You can unregister ADE and register with the correct account (if you still have details);
but then you won't be able to read books associated with the other account.
If you do a bit more digging and clarify exactly where you are at, then I can probably suggest a next step.
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You can check the internal ID associated with a book by the following irritating route ...
- open a sample DRM .epub file as a .zip file.
With some zip programs, you can just open the .epub as an archive (ev, with 7zip),
with others you will have to rename the .epub file to a .zip file first, then open it. - find the file 'rights.xml' within the zip. Probably 'META-INF\rights.xml'
- open the rights.xml file
- inside you will find a section '<user>' that looks something like
<user>urn:uuid:ff2ddc22-eca0-46c6-a84d-xxxxxxxxxxxx</user>