diff --git a/module.nix b/module.nix
index 73e384e..6919efc 100644
--- a/module.nix
+++ b/module.nix
@@ -84,7 +84,7 @@ in
         authenticate = true;
       };
       extraConfig = {
-        "SMTP_ENABLE_STARTTLS_AUTO" = "false";
+        "SMTP_ENABLE_STARTTLS" = "never";
         "SMTP_TLS" = "false";
         "SMTP_SSL" = "false";
       };