diff --git a/nixos/tests/matrix/synapse.nix b/nixos/tests/matrix/synapse.nix
index 4b9ade875a78..296480548718 100644
--- a/nixos/tests/matrix/synapse.nix
+++ b/nixos/tests/matrix/synapse.nix
@@ -200,13 +200,7 @@ in
 
             # disable obsolete protocols, something old versions of twisted are still using
             smtpd_tls_protocols = "TLSv1.3, TLSv1.2, !TLSv1.1, !TLSv1, !SSLv2, !SSLv3";
-            smtp_tls_protocols = "TLSv1.3, TLSv1.2, !TLSv1.1, !TLSv1, !SSLv2, !SSLv3";
             smtpd_tls_mandatory_protocols = "TLSv1.3, TLSv1.2, !TLSv1.1, !TLSv1, !SSLv2, !SSLv3";
-            smtp_tls_mandatory_protocols = "TLSv1.3, TLSv1.2, !TLSv1.1, !TLSv1, !SSLv2, !SSLv3";
-            smtp_tls_chain_files = [
-              "${mailerCerts.${mailerDomain}.key}"
-              "${mailerCerts.${mailerDomain}.cert}"
-            ];
             smtpd_tls_chain_files = [
               "${mailerCerts.${mailerDomain}.key}"
               "${mailerCerts.${mailerDomain}.cert}"