I too have encountered this error on my MacBook Pro. I am using LittleSnitch to monitor apps attempts to access the internet. The two or three times that I received the error, LittleSnitch had prevented an EA program (sorry the name escapes me) from accessing the Internet until I had reviewed and approved the link.
There were a large number of URLs that the program was trying to reach and while I approved them all, I received the authentication error afterwards.
I configured LittleSnitch to grant the EA program unlimited outbound access to any URL and have not had a reoccurrence of the authorization failure - so far.
Firewalls and routers may also block outbound traffic unless a rule is in place to permitt the connections.
I hope this is of some help.
Good luck!