Cannot read my download

Hi,

I have the same problem, but in my case I've already have an authorization only the program won't accept it for some books.

This is what is says exactly (i translate): 

"Impossible to download. Error in retrieving license. Problem of communication of server's licenses: 

E_ADEPT_REQUEST_EXPIRED".

I cancelled the authorization and then i did it again and for one book, even if the same message error appeared, it worked, and now I can read it! So I tried with other book but... nothing! Same error, nothing works.

Why? Help, please!