Rebuild Error: Sweep resulted in topologically invalid body. How can I determine what part of the sweep path is causing this error?

Trying to cut a semi-circular groove along the 3d sketch running across the model. I have remodeled the path several times very carefully trying different radius (currently .0625"). At this point I'm just at a loss to see what is causing the problem.

Thanks for the help.

SolidworksParts And Features