Inconsistent accessibility: base interface 'interface 1' is less accessible than interface 'interface 2'
A public construct must return a publicly accessible object.
The following sample generates CS0061:
// resolve this CS0061 by either making a public and b internal // or by making both interfaces internal internal interface a { void mf(); } public interface b : a { new void mf(); } class x { public static void Main() { } }