1)   Merak Mail Server Suite 8.3.8
Multiple awards winner mail server with ultimate features and stability. Provides you with secured Mail services, Web-Mail, Anti-Spam, Anti-Virus, Instant Messaging, GroupWare, FTP, ODBC and load balancing, monitoring and report facilities.

 2)   MailEnable Professional 1.6
MailEnable Professional Edition is a enterprise level mail server for Windows 2000/NT/XP. It supports SMTP and POP3, supports an unlimited amount of email addresses, domains, groups and mailing lists.

 3)   iNetQuery 2005
iNetQuery is a powerful Internet utility for network monitoring. Special query features, like DNS, Whois or NetStat, can be used to determine detailed information about domains, hostnames or network providers.