diff --git a/README.md b/README.md
index 90898c0..aa682fc 100644
--- a/README.md
+++ b/README.md
@@ -39,7 +39,7 @@ Following Files are important and have been changed and setup with the script:
 To add additional custom environment variables, you can add a file .env.custom and add your variables there.
 This file will not be changed from the setup script and will be used inside all containers to overwrite the existing .env and .env.local
 ```sh
-MAILER_DSN='smtp://null'
+MAILER_DSN='smtps://<username>:<password>@<smtpHost>:<smtpPort>'
 DEFAULT_LANGUAGE='de'
 ```