Microsoft Exchange Server Enterprise Edition - step-up license & software assurance - 1 server

Organizations need a reliable and secure messaging solution that enables their employees to maximize their productivity and communication efficiency. With the capabilities to support multiple, unlimited message databases, Microsoft Exchange provides a reliable, scalable messaging and collaboration environment that delivers secure messaging capabilities to recipients inside and outside your organization. It is the easy-to-manage mail server that brings people and knowledge together anytime and from anywhere.

Exchange Server Enterprise Edition, designed for large enterprise corporations, enables you to create multiple storage groups and multiple databases. It provides an unlimited message store that removes the constraints on the amount of data that a single server can manage.