Member of PUBLIC class or type is instance of a PRIVATE class or type: <member name>
Within the definition of a Public class or user-defined data type, you declared as Public a member variable that refers to a Private class or user-defined data type, or you included a Public method that returns an instance of a Private class or user-defined type. For example, in the following code, the definition of the variable B produces this error condition:
Private Type MyType
A As Integer
End Type
Public Class MyClass
Public B As MyType ' Illegal because MyType is defined as Private
End Class
Change the Public class or user-defined data type to Private, or the Private class or user-defined data type to Public.