diff --git a/src/vnet/session/application_interface.c b/src/vnet/session/application_interface.c
index 2a09909..f0722d6 100644
--- a/src/vnet/session/application_interface.c
+++ b/src/vnet/session/application_interface.c
@@ -481,6 +481,19 @@
   return 0;
 }
 
+static u8 *
+app_name_from_api_index (u32 api_client_index)
+{
+  vl_api_registration_t *regp;
+  regp = vl_api_client_index_to_registration (api_client_index);
+  if (regp)
+    return format (0, "%s%c", regp->name, 0);
+
+  clib_warning ("api client index %u does not have an api registration!",
+		api_client_index);
+  return format (0, "unknown%c", 0);
+}
+
 /**
  * Attach application to vpp
  *
@@ -501,16 +514,7 @@
   int rv;
 
   if (a->api_client_index != APP_INVALID_INDEX)
-    {
-      app = application_lookup (a->api_client_index);
-      if (!app)
-	{
-	  vl_api_registration_t *regp;
-	  regp = vl_api_client_index_to_registration (a->api_client_index);
-	  app_name = format (0, "%s%c", regp->name, 0);
-	  a->name = app_name;
-	}
-    }
+    app = application_lookup (a->api_client_index);
   else if (a->name)
     app = application_lookup_name (a->name);
   else
@@ -521,6 +525,12 @@
     return clib_error_return_code (0, VNET_API_ERROR_APP_ALREADY_ATTACHED, 0,
 				   "app already attached");
 
+  if (a->api_client_index != APP_INVALID_INDEX)
+    {
+      app_name = app_name_from_api_index (a->api_client_index);
+      a->name = app_name;
+    }
+
   secret = a->options[APP_OPTIONS_NAMESPACE_SECRET];
   if ((rv = app_validate_namespace (a->namespace_id, secret, &app_ns_index)))
     return clib_error_return_code (0, rv, 0, "namespace validation: %d", rv);