I realize this is an older thread, but I happened upon it when searching for an answer. I noticed that my MRI results weren't getting uploaded to Apple. I also had the giant red bar across the screen saying ADR Server Not Available.
My problem was that I had updated my password for GSX recently and had not put the new password into the settings of the dianostic Gateway. As soon as I updated the password I was able to authenticate and my problems dissapeared.