Error erasing authorization. (When trying to fix "E_act_not_ready")

Hi!  
I am using a Mac. I am getting the E_act_not_ready error when I try to read any book.  Your directions DO NOT work.  When I go to "Erase Authorization" I get this message: "Unable to Erase Authorization. Please try after some time."

I have tried several things: completely uninstalled Digital Editions and then Re-installed. Shut down computer. These steps are not working.

How can I erase authorization if it wont let me?

Thanks in advance!!