Originally Posted by rmm200
Just to muddy the water a bit (don't try this at home), all my master copy of books are within the Calibre Library folder, in a folder called Unsorted. Since this was never added to Calibre, it is ignored, and I can happily Add to Library from within that folder.
No need to move the folder as long as you know what it is. Having the folder there is as good as anywhere else.