diff --git a/src/bacnet/rpm.h b/src/bacnet/rpm.h
index 769fd232..5b053a81 100644
--- a/src/bacnet/rpm.h
+++ b/src/bacnet/rpm.h
@@ -195,6 +195,7 @@ extern "C" {
         unsigned apdu_len,
         BACNET_PROPERTY_ID * object_property,
         BACNET_ARRAY_INDEX * array_index);
+    BACNET_STACK_EXPORT
     void rpm_ack_object_property_process(
         uint8_t *apdu,
         unsigned apdu_len,