diff --git a/lib/ldap.c b/lib/ldap.c
index 83f1004810..09eb47c81b 100644
--- a/lib/ldap.c
+++ b/lib/ldap.c
@@ -387,7 +387,6 @@ static CURLcode ldap_do(struct Curl_easy *data, bool *done)
   }
 
 #ifdef USE_WIN32_LDAP
-  ldap_set_option(server, LDAP_OPT_PROTOCOL_VERSION, &ldap_proto);
   rc = ldap_win_bind(data, server, user, passwd);
 #else
   rc = ldap_simple_bind_s(server, user, passwd);