Does anyone have the problem with having to reboot the watch manually even though I eject it correctly from the Mac ? The watch just freezes until I manually reboot it .
I'm not sure if it's permanently frozen, because sometimes it comes back to life after 10-20 seconds or so.
Sometimes I've got impatient and done the manual reboot. Maybe it would have eventually started working again by itself.
The problem appears to be related to Garmin Express on the Mac (possibly only on 10.12, not sure about that though). Quit GE first, then eject the watch, and you should be fine. Hopefully they'll fix that bug soon.