The MailTrain Express is a kind of software for sending group email (bulk email) with full-scale function, extremely high speed and stable capacity, and it is made to send business email. It support automatic client unsubscribing. It has the advantages that numerous group-sending software have internationally, it also fits the language environments of different countries, so it is an ideal tool to send commerce information internationally. It can directly send email to specific host computer of each email address without transfering by SMTP server, which makes the other side immediately receive your mail, avoiding the transmission delay even fail under the traditional SMTP relay.