E_ADEPT_DISTRIBUTOR_AUTH

I just bought some ebooks protected with DMR on IBS. I can not download them with adobe digital edition and I receive the following error: Unable to download. License recovery error. License server communication problem E_ADEPT_DISTRIBUTOR_AUTH.
(I receive the message in Italian, I translated it, the translation may not correspond to the same message in English)

Has anyone had the same problem? Can someone help me?

Thanks a lot!