Originally Posted by jackie_w
This is an interesting work-around. Have you tried moving your Calibre library since you started doing this. I was wondering whether the Calibre-unknown formats, such as .pdf-orig, got properly moved with the known formats (epub, zip etc) for any particular book.
No, I haven't. Does "moving the library" mean simply moving the base directory someplace else? I don't think that this would have any side-effects.