E_AUTH_BAD_DEVICE_KEY_OR_PKCS12

Hello, I use a macbook and I borrowed an ebook but, once I downloaded and clicked the acsm file, Adobe Digital Editions gives me the following error:
"Unable to download: License retrieval error. Communication problem with the license server: E_AUTH_BAD_DEVICE_KEY_OR_PKCS12 "
I already tried reinstalling Adobe Digital Editions and it didn't work. I also tried several times to deauthorize ADE but I get "Unable to erase authorization. Please try after some time."
How do I solve the problem?
Thank you for your help!