.keepalive = TRUE,
.retry_include_ip_address = TRUE,
#ifndef DISABLE_TLS
+# if defined(SUPPORT_SYSDEFAULT_CABUNDLE) || !defined(USE_GNUTLS)
.tls_verify_certificates = US"system",
+# endif
.tls_dh_min_bits = EXIM_CLIENT_DH_DEFAULT_MIN_BITS,
.tls_tempfail_tryclear = TRUE,
.tls_try_verify_hosts = US"*",