MDaemon Messaging Server is a Windows-based email and groupware server developed by Alt-N Technologies, based in Grapevine, Texas.MDaemon's features include a built-in spam filter with Heuristic and Bayesian analysis, SSL and TLS encryption, public and shared folder support, mailing lists, web-based email client (WorldClient), support for sharing of groupware data (calendar, contacts, tasks & notes), over-the-air synchronization of mobile devices via ActiveSync, CalDAV, BlackBerry Internet Service, and an optional BlackBerry Enterprise Server (BES) plug-in.