It takes an eternity to upload new activities to Strava / Garmin Connect, which I believe based on googling is because my unit still has every activity on it since it started using it – so hundreds.

I’ve copied the whole Garmin directory over to my PC so I have it backed up, can i now just delete all the .tcx files from my unit, or do i have to do it through the menu on the unit itself (in which case, where’s that command located?)

I had a problem with my Edge 500 so phoned their helpline recently, number on their website, they were very helpful.

Anyway he told me how to reset it and that cleared all the old rides… Now it’s massively faster at uploading.

The reset command is different for each model apparently but it might be worth giving them a buzz.

Menu/history/delete/delete all
At least I think that’s what you are looking for

I just do a manual upload via Strava – just select the files from your history. Takes seconds.

If you delete the files, that should do it.

You can delete the files from the History folder via your PC.

It is also possible to upload courses and things the same way rather than using TrainingCentre, BaseCamp, etc.

Useful resource here.