This is what happens when I use the Copy button in a collection. I appreciate that collections are actually pointers to files, hence the error. I had hoped that there would be an option on the (raw) Copy command to handle files in collections but this does not appear to be so. Is there a way?
This turns out to be a consequence of a bug (which I will now formally report) I raised in the forum a couple of days ago whereby a button can be programmed to take you to a non-existent folder without raising an error. In this case the target was just such a folder. Everything looks fine on the Opus lister but in reality, the target folder does not exist.