diff --git a/src/apps/natdiscovery/natdiscovery.c b/src/apps/natdiscovery/natdiscovery.c
index 867926d..8fe31be 100644
--- a/src/apps/natdiscovery/natdiscovery.c
+++ b/src/apps/natdiscovery/natdiscovery.c
@@ -513,7 +513,7 @@ int main(int argc, char **argv)
 	  }
   }
   if (!filtering && !mapping) {
-  	printf("Please use either -f or -m parameter for Filtering or Mapping behavior discovery.");
+  	printf("Please use either -f or -m parameter for Filtering or Mapping behavior discovery.\n");
   }
   socket_closesocket(udp_fd);