I have several devices and I could add my devices using Garmin Express.
But when I tried to add a new device, vivosmart HR+ today, I had a Server Error message at Settings.
I clicked 'Try Again' again and again but it did not proceed to the Profile pane.
I can connect to http://omt.garmin.com and I tried to save the setting of the device on the web page of Garmin Connect according to the Edge820 case.
Now I am using Garmin Express 4.4.1.0, MacOS 10.12.1 and tried on two Macbook Air and one iMac.
I also did it on Windows 7 (Paralels Desktop 12.11) and I got Server Error several times but finally it proceeded.
vivosmart HR+ connects with iPad and I can send data to the Garmin Connect.
I will be happy if someone gives any advices on dealing with this matter.