diff --git a/tester/call_tester.c b/tester/call_tester.c
index 000c05f41..94a1a2464 100644
--- a/tester/call_tester.c
+++ b/tester/call_tester.c
@@ -364,6 +364,8 @@ static void direct_call_over_ipv6(){
 		marie = linphone_core_manager_new( "marie_rc");
 		pauline = linphone_core_manager_new( "pauline_tcp_rc");
 
+		linphone_core_use_files (pauline->lc,TRUE);
+
 		linphone_core_enable_ipv6(marie->lc,TRUE);
 		linphone_core_enable_ipv6(pauline->lc,TRUE);
 		linphone_core_set_default_proxy_config(marie->lc,NULL);