Mac OS X Softwares to Email Server

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.

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.

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.