unity 5 cloth constraints not working

after attaching a cloth component to a plane gameObject, when i click the edit constraints button
the small sub window opens with paint and select
however, no attach points(dots) show up in the scene editor on the plane.
what is going wrong??

I solved your problem:-
When you add a cloth component to a mesh , will be added automatically another component , the Skinned Mesh Renderer.
In this last component make sure that the Mesh box, is’nt empty and that it’s contain the mesh of the cloth.
After this the constraints will be visible.

This worked for me. I had to choose the right mesh to fill in that Mesh box field.