diff --git a/src/lang/en_US.h b/src/lang/en_US.h
index 9cc557b9..f506f0d1 100644
--- a/src/lang/en_US.h
+++ b/src/lang/en_US.h
@@ -57,6 +57,7 @@
 #define D_OBJECT_EVENT_UNKNOWN "Unknown Event %d"
 
 #define D_ATTRIBUTE_UNKNOWN "Unknown property %s"
+#define D_ATTRIBUTE_READ_ONLY "%s is read-only"
 #define D_ATTRIBUTE_PAGE_METHOD_INVALID "Unable to call %s on a page"
 
 #define D_OOBE_SSID_VALIDATED "SSID %s validated"
diff --git a/src/lang/nl_NL.h b/src/lang/nl_NL.h
index 1da41df2..7ed1352e 100644
--- a/src/lang/nl_NL.h
+++ b/src/lang/nl_NL.h
@@ -57,6 +57,7 @@
 #define D_OBJECT_EVENT_UNKNOWN "Onbekend Event %d"
 
 #define D_ATTRIBUTE_UNKNOWN "Onbekend attribuut %s"
+#define D_ATTRIBUTE_READ_ONLY "%s is alleen-lezen"
 #define D_ATTRIBUTE_PAGE_METHOD_INVALID "%s is ongeldig voor een pagina"
 
 #define D_OOBE_SSID_VALIDATED "SSID %s gevalideerd"