hMailServer is a truly free email server for Microsoft Windows Server. You can create as many email accounts as you needed, it also come with a lot of features that mostly you’ll find in a commercial products.
hMailServer is widely used by ISP, companies, governments and education organization. It supports common email protocols (IMAP, POP3, SMTP) and can be integrated with many existing web mail software such as: Squirrelmail and RoundCube.
Features such as SPF check, DKIM, spam protection and antivirus also available in hMailServer. It uses built-in Spamassassin for scanning spam mail and ClamWin to scan emails for viruses.
hMailServer uses database server for data storage to gain optimal performance. You can choose from MySQL, Microsoft SQL or PostgreSQL as the backend. If your email usage is very little, for personal use for example, then you can use the default database server Microsoft SQL Server Compact Edition.
hMailServer 5 can be installed on Microsoft Windows Server 2008 (all edition, except for Core), Windows Server 2003 (all editions), Windows XP and Windows 2000 (all editions). You’ll also need Database Server to store all the emails, you can choose from MySQL 4, MySQL 5, Microsoft SQL Server 2000, 2005 and 2008 (including Express, Standard and Enterprise edition) or PostgreSQL 8.
To download free email server for Windows Server “hMailServer“ you can go here: http://www.hmailserver.com/index.php?page=download