Unfortunately, I upgraded to 4.1.26.0 and now cannot sync my files. I just get the infamous "There was an error syncing with Garmin Connect" message.
I have deleted the device, a Forerunner 610, from Garmin Express and re-added it.
I see in "C:\ProgramData\Garmin\CoreService\Devices\3857441552\Sync\FIT_TYPE_4" that there are 106 files. Note that FIT_TYPE_4 is new. There is also a "FIT_TYPE_9".
Any clues?