I know this thread is a bit old and the versions have probably moved on but I have just moved over from Dropbox to OneDrive for Business as my primary destination and I am experiencing the issue in this thread. The version I have is 11.7.3 professional. I am backing up 105 databases in one job and 85 in another job. Intermittently in the backup log file I see
Destination Error: Unexpected response status code “Completed”. Status description: “Unauthorized”. Error Message: “{“code”:“unauthenticated”,“The caller is not authenticated.”}}”. ErrorException: “”.
Transfer rate gradually dropping to 300kb/s