There are separate purchasable licenses for Windows/Mac/Linux endpoint management and Chromebook management.
Each purchased Windows/Mac/Linux license allows management of one FortiClient endpoint. You must purchase a minimum of 100 endpoint licenses, and you can have these EMS licenses for a maximum three year term. You can specify the number of endpoints and the term duration at time of purchase.
Each purchased Chromebook license allows management of one Google Chromebook user. You must purchase a minimum of 100 Google Chromebook user licenses and can have these EMS licenses for a maximum three year term. You can specify the number of Google Chromebook users and the term duration at time of purchase. FortiClient EMS uses one license seat per logged-in user. If the user logs out, the license seat times out (default timeout being 24 hours), and the license is released. At this point, another user can use this license seat.
An email is sent when you are running out of licenses. Additionally, a log entry is entered when a client is refused connection due to unavailable licenses.