2015 MacBook Pro, Catalina, License Server Comm Prob - E_ADEPT-DOCUMENT_OPEN_ERROR

For five years I have found it impossible to open books in ADE. For the last four I have done my best to never buy one in that format. Now an academic publisher only makes ebooks available this way. 
I have followed the de-authorize, close, delete Library file, re-open, re-authorize instructions 20 times... I still get this error. 

Error getting License. License Server Communication Problem:

E_ADEPT_DOCUMENT_OPEN_ERROR

This is a major publisher and the book was purchased from ebooks dot com where my log in is through the same email as my Adobe ID.

Five years. I could use some help.

APR