ConnectionsNetwork connections are established to and from the ISMail SMTP server in order to receive and send messages. ISMail groups all connections made to the SMTP server as 'Incoming' connections, and all connections originating from the SMTP server as 'Outgoing' connections. Incoming connections may be used to transfer messages to accounts on an ISMail server domain, or as a source of messages that will be sent to another mail server via a subsequent outgoing connection. Outgoing connections are used strictly to transfer messages to other SMTP servers. Incoming and Outgoing connections are automatically configured in ISMail. SmartHostNormally, ISMail will send messages directly to the mail server of a recipient. A 'SmartHost', however, can be used to relay all messages to another mail server in order to workaround problems with firewalls, resolve outgoing port restrictions (port blocking), or to insure message delivery to mail servers which place various restrictions on senders (e.g. disallow dynamic IPs, use reverse IP lookups). Note: port blocking can be tested by opening a DOS window and entering 'telnet instantservers.com 25'. If an SMTP 'welcome' message appears, then port 25 is not blocked (enter 'quit' to exit this connection). If, however, a connection is not established, then port 25 may be blocked. Futher testing should be done to determine the cause of the failed connection. Adding A SmartHostTo add a SmartHost (using standard port 25):
To add a SmartHost (using a non-standard port):
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