Syncing tcx from dropbox to strava

[philipph832]

First of all, congratulations on Tapiriik. It's a really practical tool.

I have a question about it's functionality, probably more the functionality of Strava connected with Tapiriik. I want to sync older tcx, gpx and fit files from my dropbox to Strava. They have been downloaded exclusively either from Garmin or Suunto devices. All files contain activities with proper ID and activity tags. However, Tapiriik states that "Strava does not support the type of activity". I don't know what's wrong or what I would need to change in the file (see a screen grab of the first couple of lines of an exemplary tcx file, and the respective error message below).
Could it be that Strava simply does not allow to upload old files anymore? Downloading files from Strava to dropbox worked flawlessly - congrats on that.

Many thanks for your help