I have a C3D 2016 version of a dwg file that was created in 2016 and has always been in 2016.
I have a surface, numerous alignments and section and profiles.
I opened it in c3d2017 and attempted to save it and i get an error message saying "one or more objects in this drawing cannot be saved to the specified format. the operation was not completed and no file was created."
Why can't i save an earlier version to the new version.