I'm creating a SolidWorks file that consists mostly of surfacing, and ever since I suppressed the parent and unsuppressed it, many of the surface curves fail upon re-opening of the document. This forces me to go into the individual sketches, although they do not display error, the curve has failed. The sketches themselves remain blue, not indicating any error or any relation to any parent surface, and it is only when I delete a piece of the sketch that parts of the sketch show red, indicating failure. I then delete everything in the sketch, re-draw it (using convert entities,) and delete all existing relations. When I do this, the curve says its successful, and the surface returns. I then save, but the next time I access the document, the surfaces have returned to a broken state. Why is this occurring, and how can I prevent it so that I don't need to rebuild these curves every time I open the document?