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Mail server SMTP rules



To send email you have to use SMTP Authentication Method.
This rule prevent unauthorized sending email. The following error will be thrown: "550 Authentication is required for relay".

The mail domain used for authentication must match the mail domain in the FROM field.
If both mail domains don't match, the following error will be thrown: "rsp: 550 From domain must match authenticated domain"
This rule helps increasing the security of the mail server and seriously decrease the amount of SPAM emails sent.
This also minimize the risk of someone using your email account to send spam emails.

By default each email has max message size 10 MB for sending and 15MB for receiving. Messages greater than this size will be rejected by the mail server.

Outgoing Messages per Hour: 300, Recipients per Message: 200



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