Express Conversion Server - Version 4.0 Express Conversion Server provides a powerful and flexible server-based document conversion engine capable of automating the document conversion process of almost any document format into any number of commonly used file types. Express Conversion Server makes it possible to streamline communications - shaving significant costs, both in time and money, off the bottom line. As a server-based workflow software solution, Express Conversion Server gives companies and organizations the ability to deploy it as a standalone application or as a service made available to any document workflow, legacy application, company employee or business partner.