Exchange Server 2010 Standard - 5 Client Access Licenses - User
This add on pack only includes Client Access Licenses. No server software is included.

Microsoft Exchange Server 2010 helps you achieve new levels of reliability and performance by delivering features that simplify your administration, protect your communications, and delight your users by meeting their demands for greater business mobility. With new deployment and storage options, enhanced inbox management capabilities, and e-mail archiving built-in, Exchange Server 2010 helps you lower costs and enhance business outcomes.