COS (Class of Services)

COS (Class of Services)

A COS specifies which things and how they may be accessible by a web client, as well as the default for a variety of choices. A user who belongs to that COS can subsequently adjust some of these parameters using the web client’s Settings page.

To make a COS, click the CREATE NEW COS button and name it. Then, using the left-hand menu, you may adjust all of the parameters.


Features are settings that give or deny the user access to the most commonly used Carbonio components, both via browser and mobile apps. Some of them can be activated or disabled by CLI; for more details, see the section Setting Features via CLI.


Preferences are made up of general choices for each component (Mails, Calendar, Contacts).

The first is the default language for COS members to use, which includes the locale. The remaining options affect how Carbonio appears in web clients (for example, whether e-mails are displayed as conversations or the calendar shows a month or a work week) and govern the behaviour of some tasks performed by the user, such as whether new e-mail contacts are automatically added to Contacts or how frequently to check for new e-mails.

Server Groups

On this page, you may choose which servers new users can be added to the COS.


If only one server has been defined, no choice is possible.


 The Advanced Option allows you to establish user quotas, passwords, rules, and other settings.

The user quota is a collection of parameters that limit how much space a person may take up on the server or the number of contacts he can have. It also has the ability to deliver periodic warnings when the user space exceeds a predefined threshold.

Password settings allow you to customise the length, characters, and duration of user passwords. Common passwords might also be rejected.

The Failed Login Policy allows you to specify how Carbonio should behave when a user fails to log in. When three consecutive login attempts fail within 30 minutes, a normal policy may lock the user out for one hour.

The Timeout Policy governs the validity of the token.

The Email Retention Policy specifies how long emails are kept before being automatically destroyed.

Finally, when utilising an Exchange server, the Free/Busy Interop option allows you to submit O and OU records to show the free/busy user schedule.