Most websites today provide some sort of email notification for different events. Maybe a basic contact form, an ecommerce order/receipt notification, abandoned cart reach out for a customer who left midway through their shopping experience. Simply put, these notifications keep you connected with your customers. Unfortunately the system they rely on is email which does not guarantee deliveries due to many factors. One common theme we are seeing with customers on shared hosting is that the email notifications by default within WordPress use the local server to send out those messages. This works great until the 211th account on the shared hosting server gets hacked and floods the internet with spam. How does this affect you and your site? You may be using Microsoft Exchange or Google Apps for your email, but your site is using the shared mail service on that box. So when another shared account gets blacklisted, your site’s emails are in jeopardy of being denied as well.
There are a few options. In the past, you could order a dedicated IP address and have the hosting provider route your messages through your dedicated IP address. The next step would be to move to a virtual private server (VPS) which starts at around $40/mo depending on the provider and tools (like cPanel/WHM).
Lately a service provided my MailChimp has come in as a life saver these issues. Mandrill.com provides external mail delivery, managed by MailChimp. This allows a site operator to route their email notification messages through MailChimp without having to worry about the other sites on the their shared hosting. Even better, its free for up to 12,000 emails a month! Setup is pretty straightforward with WordPress support. Depending on the notifications you have configured (Gravity Forms, WooCommerce, etc) you may need to send a couple test notifications through different parts of your site but its a very low cost (or free) way to improve email/reliability.