Go to Show>NURBS Hull (its way at the bottom) and make sure it is checked...

Also Display>NURBS Components>Hulls (but that has them always on)...but another option to try.

And also for good mesure, go the Create>NURBS Primitive> (whatever you want) Option box> Edit> Reset Settings...You might have your UVs messed up, so this will fix any changes you might have saved.

Give those a try, I just messed around with it for a bit...