Microsoft Exchange Server Enterprise OVL, NL, CAL SNGL 1 licence(s)

Client access licenses (CALs)
With this license type, a CAL is required for each user or device that accesses the server software. There are two types of CALs for Exchange, both of which work with either edition of the server:

- Standard: designed to help users be more productive from virtually any platform, browser, or mobile device, with features in Exchange Server 2016 that help your users be productive no matter where they are—while helping protect your organization's data. To enable Standard CAL features for a user, the user must be licensed with the Standard CAL.
- Enterprise: designed to allow organizations to reduce the cost and complexity of meeting compliance requirements with new integrated archiving functionality and information protection capabilities, while also helping you cut costs by replacing legacy voice mail systems with Unified Messaging. The Enterprise CAL is sold as an add-on to the Standard CAL—to enable Enterprise CAL features, the user must be licensed with one Standard CAL plus one Enterprise CAL.