CleanMail Server Free

CleanMail is a complete and versatile SMTP/POP3 email security solution (anti-spam/anti-virus) that easily integrates into existing email environments. CleanMail includes a comprehensive set of filters, including an attachment blocker, remote blacklist filter (DNSBL), and a complete Windows build of the award-winning, open-source SpamAssassin filter. The open-source ClamWin anti-virus package is available as a fully-integrated, optional download. CleanMail also supports anti-virus software packages by many 3rd party vendors.
With CleanMail you have online access to view real-time statistics charts and reports using a web browser, or using the CleanMail Admin application. Data available online includes spam statistics, mail logs (a listing of mails received, including subject, sender and recipient address), and a ranking of spam hosts (hosts submitting spam mails ie. in the last 24 hours).
Additional features include traffic limiting (to protect your mail service from directory harvest attacks and mail backscatter), mail archiving (to quarantine dubious messages, or to meet legal or regulatory obligations), and email notification (to alert about conditions that need administrator attention).
CleanMail's highly versatile filter pipeline provides an open interface that allows integrating custom mail filters, such as tools for email classification, automated mail processing, or server-based email encryption.
CleanMail is available as freeware for personal and non-commercial use. A range of commercial licenses is available, offering exceptional value at low prices. The purchase of a license includes maintenance and updates for 12 months. Renewal licenses are available at a discount. Communities or non-profit organizations please inquire for special discounts.