diff --git a/buffet/registration_status.cc b/buffet/registration_status.cc
index 4fb1721..3b44ae3 100644
--- a/buffet/registration_status.cc
+++ b/buffet/registration_status.cc
@@ -18,6 +18,8 @@
       return "registering";
     case RegistrationStatus::kRegistered:
       return "registered";
+    case RegistrationStatus::kInvalidCredentials:
+      return "invalid_credentials";
   }
   return "unknown";
 }