Disliked
The .set extension is not on the list of known file types at FF, so you correctly get an "Invalid file" error.
To upload a .set file add .txt onto the end of your file so you get something like myfile.set.txt. Then whoever downloads it just removes the .txt
Hope this helps -Ignored
So, you have to delete everything in the file´s name after .set
Good luck,
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