I use Davis Vantage Pro2 Plus, Davis Instruments WeatherLink USB data-logger and of course WD.
My computer saw the com port but would not see the data-logger and the updating data-logger window would hang. WD would eventually load but without the data in the logger. My interval was previously set at one minute. So I changed to I think 5 minutes (I don’t think that it matters), saved and closed WD. Rebooted computer. Set interval back to one minute, saved, restarted and WD saw the data-logger on Com 3.
I can’t explain why but it did the trick for me.
Terry