Hey Michael. It's me again. (Heavy sigh)

I have a somewhat complicted curve that I want to extrude into a solid. I've tried to make sure the curve is a single entity, including doing a rebuild on it. When I click on it, it says that it is a single curve. Yet, when I try to extrude into a flat, thin solid, it won't cap the ends. I'm sorry that I keep having trouble with these basic operations, but I do. I also don't seem to be able to detect what the problems on my own. Please look at it.
Thanks,
Mark