GE 6.2.0.0 on Windows 10, Edge 1030 with 3.90 FW. I've had several instances lately where I finish a ride, save it, connect the GPS to the PC and wait for it to transfer to mass storage mode, run Garmin Express, it tells me that it's synced, but when I look at Garmin Connect, the ride isn't there. I can sync again, and GE again tells me that it's sync ok, but the ride is still not uploaded.
If I turn on Bluetooth on the Edge and my phone, and run Garmin Connect Mobile, it syncs the ride without any problems. I normally don't have Bluetooth enabled on the 1030 because it still has too many problems.