Hello,
Garmin Express 5.6.2.0 doesn't recognize my Forerunner 305 on macOS High Sierra 10.13 Beta (17A360a). It seems that the problem started when I upgraded to macOS 10.13 beta.
When I connect my Forerunner 305 it beeps as if it was recognized but Garmin Express keeps showing the grey dot and actually freezes my computer for a couple of seconds and seems to briefly turn on and off my bluetooth.
Does anyone have this kind of issue? I know it's a beta version of macOS, so I'm hoping this will be solved when the final version is released, but perhaps there's a workaround? I've tried to connect my garmin on Windows and it worked, so it seems to be related to Mac only.
UPDATE: The same thing happens on macOS High Sierra 10.13 Gold Master Candidate.