Gaiaz Iusipov

This plugin gives you the easiest way to send emails through the Yandex SMTP server instead of PHP mail().
This plugin requires at least PHP 5.4 and PHP mod_ssl to be enabled

Yandex Mail

This plugin gives you the easiest way to send emails through the Yandex SMTP server instead of PHP mail().

Ozan Canakli

Yandex Mail SMTP Server for WordPress allows you to configure and send all outgoing emails via a Yandex SMTP server instead of PHP mail(). This will guarantees delivery of your emails also prevent your emails from going into the junk/spam folder of the recipients. 
* Note yandex mail account required!
This plugin also works with Yandex Mail for Domain, a free service for setting up email on your own domain.
Most shared hosting servers have restrictions when it comes to email. Usually email will get blocked or missing for no reason. Sometimes it will get blocked when your website reaches the daily limit of outgoing email. This plugin can bypass this issue by routing the email through Yandex’s SMTP server.

Yandex Mail SMTP Server for WordPress

Connect to Yandex SMTP server to automatically send emails from your WordPress site through the Yandex SMTP server instead of PHP mail().

Yandex Mail vs Yandex Mail SMTP Server for WordPress