Short description of MailScan for SMTP Servers 5.6a: MailScan 5.6a for SMTP is the world's most advanced AntiVirus and AntiSpam Solution for Mail Servers that work on platforms like Windows, Unix, Linux, Novell and Solaris. It's installed on a Windows machine to act as a Security Gateway between your Mail Server and the Internet. MailScan 5.5 offers powerful features like Web Based Administration, Non Intrusive Learning Patterns and LDAP Authenticated Web Administration.