I have a certain drawing that will not let me choose any plot style except stb files. my ctb files do not show up. they only work around was to wblock the objects to a new drawing and the copy the border and vports in and this allow me to be able to choose my ctb files. when I wblocked the entire drawing it still only allow me to choose a stb file. I believe the oringnal dwg was created in r14 but not sure. Any suggested on how to make the ctb files available on these drawings.