Use this tab to configure incoming email communication through SMTP. Work with your mail server administrator, such as Microsoft Exchange administrator, to configure these values.

Local IP address: Type the IP address of the local interface used for SMTP input. If empty, all local interfaces are used. For Windows failover cluster deployments, use the IP address of the cluster.

SMTP port: Type the port for incoming SMTP messages.

Source IP filter: Type the SMTP connections filtering rules for filtering the incoming connection requests. Each line in this field defines a rule and starts with an Allow or Deny keyword followed by the CIDR (Classless Inter-Domain Routing) notation of an IP range. These rules are compared with the source IP address of a request. For example, use Allow 10.20.30.0/24 to allow requests from IP addresses 10.20.30.0 to 10.20.30.255. By default, no filter is defined and SMTP connections are allowed from all IP addresses.

SSL/TLS active: Select if / when to use SSL for inbound email communication. See SSL certificate tab.