diff --git a/lib/base/configobject.cpp b/lib/base/configobject.cpp
index 37446413e..0cfa71b93 100644
--- a/lib/base/configobject.cpp
+++ b/lib/base/configobject.cpp
@@ -130,7 +130,7 @@ void ConfigObject::ModifyAttribute(const String& attr, const Value& value, bool
 	int fid = type->GetFieldId(fieldName);
 	Field field = type->GetFieldInfo(fid);
 
-	if (field.Attributes & FAInternal || field.Attributes & FANoModify)
+	if (field.Attributes & FAInternal || field.Attributes & FANoModify)
 		BOOST_THROW_EXCEPTION(std::invalid_argument("Attribute cannot be modified."));
 
 	if (field.Attributes & FAConfig) {