I had Digital Editions 3 on a Win 10 notebook. I installed ver 4.5 and now the program has no books in the library. When I use the file menu the program stops working. I get a message from windows that the prgram has stopped.
Closed Digital Edition.Rename the folder of My digital edition in you Documents.
Then open digital ediiton again.
I found that I had to wait. After about 5 minutes all the epub files appeared in the library.
Good as well.
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