Curve

[[Ja...]]

It's been a long time since I have worked with curve. I sectioned my model to create a yellow line where I want a 2D curve. I clicked on the yellow line to turn it red. I clicked on Curve and a 2D curve is created. When I open the feature and then close it, I get a message "The nominal points lie exactly on a line which is not allowed. Please use a 2D line or a 3D curve.". Any idea why that is? I have a feeling I am forgetting something. 

[[Cl...]]

I see this happen when the "Curve" or a section of the curve is a straight 2d line. I ignore it.

[[Ja...]]

Yeah, they are straight lines. Thank you.

[[Cl...]]

It could be the case that when you sliced the model and generated the curve it overlapped on an existing wireframe.

Then when you picked the curve, you accidently clicked the line. If that's the case, try moving the curve up or down

off of any existing wireframe and pick it again to see if that error repeats.