Apps to Email Server

Kloxo (Lxadmin) was a free and open-source web hosting control panel designed for managing servers and hosted services on Red Hat and CentOS Linux distributions. Although discontinued, it offered a comprehensive suite of tools for server administration, domain management, email services, and more, primarily targeting shared and dedicated hosting environments.

Sophos UTM (Unified Threat Management) provides comprehensive network security by integrating a firewall, intrusion prevention, web filtering, email security, and more into a single appliance. It offers a robust and affordable solution for businesses of all sizes looking to protect their network infrastructure from modern threats.

iRedMail is a comprehensive, free, and open-source mail server solution designed for ease of deployment and maintenance. It bundles popular components like Postfix, Dovecot, and Roundcube, providing robust email, calendar, and contact management capabilities.

Zarafa is an open-source groupware and email server platform, providing powerful collaborative features similar to Microsoft Exchange but with flexibility and cost advantages. It offers email, calendaring, contacts, and task management.

Endian Firewall Community is a powerful, open-source Unified Threat Management (UTM) solution designed to provide comprehensive network security. It integrates firewall, gateway, VPN, web security, and email security features into a single, easy-to-manage appliance.

MDaemon Messaging Server is a comprehensive email server solution designed for businesses of all sizes. Offering robust security, flexible deployment options, and integrated collaboration tools, it provides a powerful alternative to cloud-based email services.

AOL Mail is a free web-based email service offering reliable communication tools, generous storage, and integrated features like calendar and cloud storage, suitable for individuals and small businesses seeking a straightforward email solution.

Microsoft Exchange Server is a robust mail and calendaring server designed for businesses of all sizes, providing enterprise-grade email, calendaring, and contact management capabilities.

arkOS was a Debian-based Linux distribution designed for easily self-hosting web services and applications. It aimed to simplify the process of running personal servers for tasks like file storage, email, and website hosting.

Dovecot is a leading open-source IMAP and POP3 email server renowned for its strong focus on security, reliability, and performance. It provides a robust foundation for managing email storage and access on Linux/UNIX-like systems, catering to individuals and large organizations alike.

Postfix is a widely used and highly regarded open-source mail transfer agent (MTA) designed to be a significantly more secure and robust alternative to Sendmail. It handles the routing and delivery of email, acting as the central hub for your organization's or system's email flow.

hMailServer is a robust and free open-source email server designed for Microsoft Windows environments. It provides comprehensive support for standard email protocols like POP3, IMAP, and SMTP, making it a versatile solution for both small businesses and individual users needing a self-hosted mail service.

Horde Groupware is a free, web-based suite of applications designed for collaboration and productivity. Built on the robust Horde framework, it offers a comprehensive set of tools including webmail, calendar, task management, and note-taking, providing an integrated platform for individuals and teams.

Kopano is a versatile open-source groupware suite offering email, calendaring, contacts, and online collaboration tools for businesses and organizations. It provides flexible deployment options, including on-premises and hosted solutions, with strong focus on data privacy and security.

Email.biz offers a secure and privacy-focused email service designed for businesses and individuals prioritizing data protection and generic domain identities. It provides essential communication tools including encrypted email, calendar, and contact management, with integrations for enhanced productivity.

Zimbra Collaboration Suite is a comprehensive open source email and collaboration platform designed for businesses. It provides a secure and feature-rich environment for email, calendaring, contacts, tasks, and file sharing, supporting on-premises and cloud deployments.

SOGo is a powerful open-source groupware server designed for scalability and simplicity. It provides a comprehensive suite of collaborative features including webmail, calendaring, contact management, and task management, with strong support for standard protocols like CalDAV and CardDAV.

ClearOS is a robust Linux distribution serving as a comprehensive server solution for small to medium-sized businesses. It provides a unified platform for networking, gateway, and server functions with a user-friendly web-based interface.

Kolab Community is a comprehensive, free, and open-source groupware suite designed for collaborative work. It provides integrated email, calendar, contacts, and tasks functionalities, empowering individuals and teams to communicate and manage their data efficiently and with a strong focus on data privacy.