The authoring tool comes with a module called Mailer for sending emails (read more about Mailer here), but before you can use it, you need to configure an SMTP server.

Don't worry, Mailer uses the popular Nodemailer module to take care of the mail transport nitty-gritty; all you need to do is to configure it. A bunch of popular services are supported out-of-the-box, so the chances are all you need to do is add your details to the conf/config.json file.

See the following section in the Configuring the Authoring Tool page which attributes are needed for SMTP.

For instruction on configuring other services, see the Nodemailer documentation.