The steps needed to establish a connection for sending electronic messages via Mandrill can be found below:
- Create an account in Mandrill with the free marketing plan and additional purchase of individual blocks of transactional e-mails
 - Add the domain from which messages will be sent and fix DNS records in the Mandrill account
 - Add message templates for sending notifications in the Mandrill account
 - Establish the Mandrill connection
 - Activate the option of sending webhooks in the Mandrill account
 - Configure sending events in additional settings
 - Enabling capturing of product images and links for sending via e-mail.
 
Errors when enabling and sending
1. check DNS and DKIM settings.
OK
ERROR: edit domain settings
Add the domain from which messages will be sent and fix DNS records in the Mandrill account
2. The following error is displayed for e-mails sent: rejected recipient-domain-missmatch
Check the above-mentioned settings under point 1. and check whether you have a standard package purchased. Namely, the error occurs when our Mandrill account is still in the free trial period.