Can't remove material/ remove material is greyed out

[Bart_Water]

I have a problem with removing material in Creo Parametric 7.1.

The remove material setting is inactive.

The first feature is solid as you can see.

Strange situation, in Inventor it works fine.

The plane on which the sketch is located is tangent to the cylindrical surface below.

[Tdaugherty · Accepted solution]

Are you sure that the geometry you're extruding on is solid? It looks like it isn't to me... That would explain what you're seeing.