Then it got worse, and even multiple refreshes of the page did not help. Now and then, I had to refresh the Libby download page two, or even more times, in order for ADE to successfully fulfill the EPUB file. If I refreshed the book download page, everything would work normally, just the way it used to. License server Communication Problem: FILE_DOESNOT_EXIST' - but only if ADE was already open (for example, if this was the SECOND book I was trying to download). On the new machine, I noticed that with the exact same procedure described above, ADE would often return the error 'Unable to download. Then I recently got a newer, much faster Windows 11 machine. Firefox then automatically opens the ACSM file, which launches Adobe Digital Editions (ADE, currently Version 4.5), which then fulfills the EPUB book file.

Once I check out the book, I select the EPUB format and the web browser (Firefox several recent versions over the past year, running under Windows 10) downloads the ACSM file. I've been using the Libby app to download library books in EPUB format for over a year, with no problems.

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