Lumisoft Mail Server

Lumisoft Mail Server is an open-source, free mail server that can run on. net/mono, supports SMTP/POP3/IMAP4/webmail, ms SQL Server, PostgreSQL/XML, and other data storage methods. it is suitable for small and medium-sized enterprises, and has no problems in stability and compatibility.

1. The system is more stable Based on the Microsoft. net2.0 platform.
2. Provides scalable interfaces that can be seamlessly integrated with applications.
3. database storage is supported. Currently, database systems such as sqlserver2000/2005 are supported, and scalable interfaces are provided to allow automatic storage.
4. supports access by a large number of users. The system adopts an open architecture and supports more than one million users.
5. Supports the multi-domain name and multi-Mailbox SMTP address functions.
6. Supports SMTP, ssl smtp, POP3, SSL POP3, IMAP4, SSL IMAP4, webmail, and other protocols.
7. Supports the HELO/EHLO host name filtering function.
8. Supports the automatic restriction function for sending mails outdoors (for accounts ).
9. Supports Reverse Domain Name verification when receiving emails through SMTP.
10. Support for relay forwarding.

There are also FTP/DNS/ICMP/HTTP/nntp/POP3/SMTP and other protocols.

Http://www.codeproject.com/useritems/SMTP_POP3_IMAP_server.asp