Hi there! I was in a similar situation and found something that worked for me:
- When the "lending" of the book expires, DO NOT DELETE ANYTHING. Just leave it on your library, like a zombie.
- Download the book again (in my case, borrow it again from my university library). Now you should have two versions of the same book in your ADE library: the old expired one and the fresh new one.
- Open the new version, highlight just anything and close it again.
- Go to C:\Users\<username>\OneDrive\Documentos\My Digital Editions\Annotations (or something similar on your PC).
- Find the ".annot" documents with the title of your book. There should be two, in my case "Risikogesellschaft" for the old version and "Risikogesellschaft-1" for the new version.
- Replace the title of the new version to just anything (I didn't dare to delete it, you possibly could), and replace the title of the old version with the title of the new version (in my case, "Risikogesellschaft" becomes "Risikogesellschaft-1").
- Open the new version of the book on Adobe Digital Editions and check if the highlights and annotations are there.
I really really hope this works! And I hope I didn't make any mistakes in the instructions 🙂