Mimecast Secure Email Gateway - Prevent targeted email-borne attacks with Mimecast Secure Email Gateway for cloud-based anti-virus and anti-spam protection.

Zoho Mail - Zoho Mail is a secure, encrypted, and enterprise-ready email solution, a suite of apps tailor-made for your organization's needs.

FortiMail - Fortinet Email security is designed to block ransomware, phishing, and other cyber threats seeking entry via incoming email and outgoing messages don’t improperly leak sensitive data.

FastMail - Email, calendars, and contacts to highest standards of security, privacy and reliability.

Proxmox Mail Gateway - Protect mail server against spam, viruses and malware with Proxmox Mail Gateway security for businesses, government, education and non-profit organizations.

QQ Mail - QQ Mail is an enterprise email solution from Tencent.