diff --git a/ldapauthenticator/ldapauthenticator.py b/ldapauthenticator/ldapauthenticator.py
index c195786..03cdf1a 100644
--- a/ldapauthenticator/ldapauthenticator.py
+++ b/ldapauthenticator/ldapauthenticator.py
@@ -513,6 +513,9 @@ def authenticate(self, handler: web.RequestHandler, data: dict) -> typing.Option
                 search_scope=ldap3.SUBTREE,
                 attributes=self.user_membership_attribute if self.allowed_groups else list(),
                 paged_size=2)
+            
+            # remove all searchResRef from response
+            conn.response = [search_ref for search_ref in conn.response if 'type' in search_ref and search_ref['type'] != 'searchResRef']                       
 
             # handle abnormal search results
             if not conn.response or len(conn.response) > 1: