This add-on integrates the MailerSend (aff) mail delivery service with the Newsletter plugin.
The MailerSend Addon is free, you can install it from the Addons page on the Newsletter plugin administration side of your WordPress blog or by downloading the zip package from your account page at thenewsletterplugin.com and installing it as a regular plugin.
To use MailerSend delivery service you need an account (both for the free or paid plans) and a validated domain: MailerSend provides a step-by-step procedure to validate the domain you want to use as the sender address for your newsletter.
For example, if the sender address is newsletter@mynicedomain.com, you should validate “mynicedomain.com”. Validation requires the modification of your DNS, you can ask for support to your hosting provider.