I got this message:
Failed to authorize using the OAuth service: The remote name could not be resolved: ‘duplicati-oauth-handler.appspot.com’. If the problem persists, try generating a new authid token from: Duplicati OAuth Handler
Then I updated the auth token and got this message:
Unexpected difference in fileset version 8: 12/1/2018 5:00:00 AM (database id: 100), found 1527774 entries, but expected 1527775