diff --git a/bacnet-stack/demo/handler/s_whohas.c b/bacnet-stack/demo/handler/s_whohas.c
index 8b00502a..5ff4fef8 100644
--- a/bacnet-stack/demo/handler/s_whohas.c
+++ b/bacnet-stack/demo/handler/s_whohas.c
@@ -84,6 +84,7 @@ void Send_WhoHas_Object(int32_t low_limit,
     int32_t high_limit,
     BACNET_OBJECT_TYPE object_type, uint32_t object_instance)
 {
+    int len = 0;
     int pdu_len = 0;
     BACNET_ADDRESS dest;
     int bytes_sent = 0;
@@ -95,13 +96,18 @@ void Send_WhoHas_Object(int32_t low_limit,
         return;
     /* Who-Has is a global broadcast */
     datalink_get_broadcast_address(&dest);
+    /* encode the NPDU portion of the packet */
+    npdu_encode_npdu_data(&npdu_data, false, MESSAGE_PRIORITY_NORMAL);
+    pdu_len = npdu_encode_pdu(&Handler_Transmit_Buffer[0], &dest,
+        NULL, &npdu_data);
     /* encode the APDU portion of the packet */
     data.low_limit = low_limit;
     data.high_limit = high_limit;
     data.object_name = false;
     data.object.identifier.type = object_type;
     data.object.identifier.instance = object_instance;
-    pdu_len = whohas_encode_apdu(&Handler_Transmit_Buffer[0], &data);
+    len = whohas_encode_apdu(&Handler_Transmit_Buffer[pdu_len], &data);
+    pdu_len += len;
     bytes_sent = datalink_send_pdu(&dest, &npdu_data,
         &Handler_Transmit_Buffer[0], pdu_len);
 #if PRINT_ENABLED