All of a sudden, my D2 Charlie has stopped connecting to any computer (I've tried 2 Macs and an older PC on Windows 10). The watch will charge via the USB plug, but will not connect to the computer; in hopes of using Garmin Express. I am now on 5.60; and have no problem connecting to Garmin Connect on my iPhone (except when the phone is powered off and the app resets itself). I have tried a hard reset. I have ordered a new cable and confirmed that it works properly with other devices. I can successfully connect other Garmin devices to the computer and use Garmin Express. I have toggled USB mode from Mass Storage to Garmin and back again. For the longest time; it was stuck trying to update an app (was stuck in Connect Mobile with Sending Update); but that appears to have ended. I don't know what else it could be.