I have changed my email and password on the Adobe Website. Then I found that my Adobe Digital Editions Desktop App is still associated with my old email address and my old password (which I no longer have)
When I try and associate it with my new email and password it will not let me because I don't have the original password.
I have tried deleting it and downloading it again but it is the same thing
Did you ever get an answer to this? I have the same problem!!
Found this worked from where someone else had asked - just incase you are still stuck:
Close all applications.
Press WINDOWS + R.
In the Open text box, type regedit and then press Enter. The Registry Editor opens.
In the left pane of the Registry Editor, locate the following registry key: HKEY_CURRENT_USER\Software\Adobe\Adept
Remove the Adept Folder.
In the Confirm Key Delete dialog, click OK.
Close the Registry Editor.
Open Adobe Digital Editions and reauthorize..
quit Adobe Digital Editions.
Navigate to /Users//Library/Application Support/Adobe/Digital Editions and drag the activation.dat file to the trash.
If you are using 10.7, see https://helpx.adobe.com/x-productkb/global/access-hidden-user-library-files.html
Open Adobe Digital Editions and reauthorize.