There are conflicting XmlnsCompatibleWithAttributes in assemblies '{0}' and '{1}' for OldNamespace '{2}'. Change the attributes ...

There are conflicting XmlnsCompatibleWithAttributes in assemblies '{0}' and '{1}' for OldNamespace '{2}'. Change the attributes to have the same NewNamespace, or pass a non-conflicting set of Reference Assemblies in the XamlSchemaContext constructor.