About SMTP

SMTP stands for Simple Mail Transfer Protocol and is the standard for sending e-mail messages between servers or from a mail client to a mail server.

When you configure any e-mail application (e.g. Outlook Express, Mozilla Thunderbird, Eudora, etc.), you must specify the SMTP or outgoing mail server as well as the POP3 or IMAP server for accessing your Inbox. 

You must enter a valid SMTP server setting in your e-mail client programme to be able to send messages, even though you may be able to receive incoming mail normally.

The SMTP server used must be the one belonging to the provider on which you rely for the connection, i.e. if you connect internally to the EUI LAN (PC-LAN connection ), or dial direct into the EUI (PPP Modem Connection ), or enter the EUI network via VPN , then your SMTP setting should be smtpmx to use the EUI server for sending.

If, instead, you access your EUI e-mail via a third-party Internet service provider such as tin.it, aol,etc., or you subscribe to ADSL broadband, then enter the name of the SMTP server communicated to you by the ISP, telephone company, or whoever maintains the (non-EUI) network from which you connect.

These constraints are for security. A server which acts as an 'open relay', passing messages originating elsewhere and destined for somewhere else again, is vulnerable.

Spammers use relaying and the EUI, like most e-mail providers, does not allow the transmission of outgoing messages coming from an external domain (you get an error report stating 'We do not relay').

Therefore you must set your SMTP server as belonging to the domain from which you send your messages.