About listener accounts

Listener accounts are accounts that subscribe to notifications for users against Exchange Web Services (EWS) to detect new mail and calendar invites.

Listener accounts must use specific impersonation rights for real-time mail notification integration. Each listener account must use the following permissions:
  • Member of Domain Users
  • Impersonation permissions on your Client Access Server (CAS)

Each listener account monitors up to 1,250 mailboxes. You can configure a maximum of 12 listener accounts for each Cloud Extender®, which equals a maximum number of 15,000 mailboxes monitored by each Cloud Extender.