There is a link called Definitions (see Figure 3.26) to define characteristics of the e-mail server:
Maximum e-mail size
Maximum time to hold the message in the server
Maximum number for simultaneous SMTP connections
Incoming message timeout
Outgoing message timeout
Reject emails from invalid domains
Reject emails from invalid servers
In this interface it is even possible to define permissions of sending and receiving e-mails:
Valid internal recipients A list with valid e-mail addresses. Valid addresses are e-mails with recipients of this list and e-mails accepted by the server.
Note: Only e-mails with addresses that are introduced as valid internal recipients in the list will be delivered.
Invalid senders A list with e-mail addresses that are not allowed to send e-mails.