File: //usr/share/webmin/postfix/help/opt_smtp_data_xfer_timeout.html
<header>Timeout on waiting for answer to transmit of message content</header>
<center><tt>smtp_data_xfer_timeout</tt></center>
<hr>
This parameter specifies the SMTP client timeout in seconds for sending the
SMTP message content. When the connection stalls for more than
<tt>$smtp_data_xfer_timeout</tt> the SMTP client terminates the transfer.
<p>
In case of problems the client does NOT try the next address on the mail
exchanger list.
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