I have a 110 and upload my data to MapMyRun. I've also had trouble but work around it by uploading a file rather than selecting the Garmin option. Maybe there's an update you need. The Garmin website might have a fix.
I have found that you need to connect the watch to the cable BEFORE you plug the USB cable in to your computer. It should then see the watch as an external hard disk drive and you can browse the contents in explorer (or finder if you use a mac).
If you make sure you can see the watch in explorer/finder before you try transferring the data using Garmin Connect or Training Centre you should be fine
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Have you added the device to GTC or are you using GC for your data?
If you make sure you can see the watch in explorer/finder before you try transferring the data using Garmin Connect or Training Centre you should be fine