diff --git a/src/applications/auth/controller/config/PhabricatorAuthEditController.php b/src/applications/auth/controller/config/PhabricatorAuthEditController.php
--- a/src/applications/auth/controller/config/PhabricatorAuthEditController.php
+++ b/src/applications/auth/controller/config/PhabricatorAuthEditController.php
@@ -31,6 +31,8 @@
 
       $is_new = false;
     } else {
+      $provider = null;
+
       $providers = PhabricatorAuthProvider::getAllBaseProviders();
       foreach ($providers as $candidate_provider) {
         if (get_class($candidate_provider) === $provider_class) {