AfterLogic XMail Server Pro for Windows

From iForum:

AfterLogic XMail Server Pro is an easy-to-use mail server for Windows and Linux. Check mail online with the fast and user-friendly AJAX webmail packed with a number of stylish skins, access and manage mail folders, browse e-mails with a preview pane and compose new ones with a rich-text editor, use address book to easily send mail to individual contacts or groups. And you can also check POP3/IMAP accounts on external mail servers. The integrated calendar lets you schedule any events, share them with the selected colleagues or even make them available to public. With the web administration panel, the admin can quickly create or manipulate domains, users and the server settings. In addition to the AJAX-enabled web interface for modern browsers, XMail Pro fully supports desktop mail clients and implements POP3, IMAP, SMTP protocols (including SSL/TLS and SMTP authentication). It also supports "static HTML" mode if AJAX functionality is not available or disabled for security reasons. Security options also include blocking external images and javascript code in e-mails being viewed. Other features include: unlimited domains, account and domain aliasing, spam protection (Bayesian filter, DomainKeys, black lists), antivirus integration, mailing lists, logging, remote administration, filters, forwarding, custom mail processing. The web part (webmail and admin panel) is written in ASP.NET (v2.0 or above is supported) and comes with the Source Code which can be modified for your needs.