Hi william, it helps a lot if you can post a 3DM model file instead of just a screenshot. That then makes it possible to analyze things about the model that really can't be seen just in a screenshot alone.

But probably like Brian mentions above, you may be selecting curve objects when trying to do the blend. You need to select an unattached edge curve for the kind of blend you're doing instead of a "standalone" curve object.

If you have any construction curves overlapping those same areas you are trying to blend, select the curves and delete or hide them to get them out of the way so that you can select the edges instead.

- Michael