AWS IoT Device Defender - Manage the security of your fleet. With AWS IoT Device Defender, you can audit and monitor device configurations. Get started today.
Emails - Simple, easy and secure mail server with a convenient and simple interface.
Azure Sphere - Help protect your connected IoT devices, such as MCUs and crossover modules, development kits, and guardian devices, with Azure Sphere.
hMail Server - hMailServer is a free e-mail server for Microsoft Windows.
Symantec Critical System Protection - Symantec Critical System Protection is a flexible and compact behavioral security engine built with application whitelisting infused with anti-exploits for managed or standalone IoT devices.
iRedMail - A fully fledged, free email server solution, an open source project (GPL v2).