Best Mail Servers for Thunderbird

SmarterMail is the ideal Microsoft Exchange alternative. First, it's the only business email server on the market that offers native support for the protocols that power Exchange: MAPI, EWS, and EAS. It does this without the need for any additional software or plug-ins for Microsoft Outlook or other clients -- desktop and mobile! Best of all, it offers all of the features of Exchange, but at a FRACTION of the cost. In addition, features like audio and video group chat, and Online Meetings for team meetings and group collaboration are included at no extra charge. It's designed to provide the functionality businesses need, without sacrificing secure, reliable access to business, and personal, communication.

SOGo is a reliable and well-supported groupware server designed with an emphasis on scalability and adherence to open standards. Released under the GNU GPL/LGPL v2 and later, SOGo features an advanced AJAX-based web interface while accommodating various native clients by utilizing standard protocols like CalDAV, CardDAV, and GroupDAV, in addition to Microsoft ActiveSync. Acting as the crucial link within your infrastructure, SOGo provides users with a cohesive and comprehensive interface for accessing their data. Its effectiveness has been demonstrated in production settings that cater to thousands of users, ensuring robust performance and efficiency. Overall, SOGo enhances collaboration and information retrieval within organizations of any size.