diff --git a/config/application-example.yml b/config/application-example.yml
index b7ce232ac..dfd9d4047 100644
--- a/config/application-example.yml
+++ b/config/application-example.yml
@@ -44,6 +44,8 @@ smtp_password: 'pw/key'
 smtp_domain: 'domain for HELO checking'
 # Use "none" only when for a self-signed and/or wildcard certificate
 smtp_openssl_verify_mode: 'peer' # 'none', 'peer', 'client_once','fail_if_no_peer_cert'
+# Detects if STARTTLS is enabled in your SMTP server and starts to use it. Defaults to true.
+smtp_enable_starttls_auto: 'true' # 'false'
 
 # autotest config overwrites
 test:
diff --git a/config/application.rb b/config/application.rb
index 84bfb61f3..f597fd890 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -61,12 +61,12 @@ module Registry
     config.action_mailer.smtp_settings = {
       address: ENV['smtp_address'],
       port: ENV['smtp_port'],
-      enable_starttls_auto: true,
+      enable_starttls_auto: ENV['smtp_enable_starttls_auto'],
       user_name: ENV['smtp_user_name'],
       password: ENV['smtp_password'],
       authentication: 'smtp_login',
       domain: ENV['smtp_domain'],
-      openssl_verify_mode: ENV['smtp_openssl_verify_mode']
+      openssl_verify_mode: ENV['smtp_openssl_verify_mode'],
     }
   end
 end