Our website provided a free download of ListStar 2.3 for Mac. The software belongs to Communication Tools. Our antivirus scan shows that this Mac download is clean.
From the developer:
ListSTAR is an automated email processor for the Mac that allows you to create and maintain Internet-style mailing lists (listservers), automated email response systems (EMail-On-Demand), and direct mailing lists on the Internet. The underlying technology is an email rules engine specifically designed to perform complex and automated mail services on your Mac.
You may want to check out more Mac applications, such as Installer OS X El Capitan, which might be related to ListStar.