Use this dialog box to create an Exchange Mailbox client. You can create an Exchange Mailbox client in a Database Availability Group (DAG) environment or a non-DAG environment. Use the Access Nodes tab to associate the access nodes (proxy clients) with the Exchange Mailbox client.
Clients
The list of access nodes that are associated with the Exchange Mailbox client.
Add
Clicking Add opens the Select Clients/Client Groups dialog box so that you can associate access nodes with the Exchange Mailbox client.