diff --git a/doc/ADMIN.md b/doc/ADMIN.md
index 2cb06f7..6894d23 100644
--- a/doc/ADMIN.md
+++ b/doc/ADMIN.md
@@ -2,4 +2,6 @@ The password-file is created after first opening the admin UI!
 
 Be sure to immediately change the default password!
 
-Open the admin UI `https://__DOMAIN__/__PATH__/?admin` to configure your mail server settings. Login with user "admin" and password from the file `__INSTALL_DIR__/data/_data_/_default_/admin_password.txt`.
+Open Snappy's admin UI `https://__DOMAIN__/__PATH__/?admin` to configure your mail server settings. Login with user "admin" and password from the file `__INSTALL_DIR__/data/_data_/_default_/admin_password.txt`.
+
+In particular, to be able to send emails, you need to go to Snappy's admin UI > Domains > __DOMAIN__ > SMTP > Check "Use authentication"