On Wed, 26 Apr 2006 13:04:00 -0300, Bruno Robichaud
<[log in to unmask]> wrote:

>26 Apr 2006 08:42:57 Send error: Unknown error [10053]
>26 Apr 2006 09:49:56 Receive error: Unknown error [10053]
>26 Apr 2006 10:06:53 -> RSET
>
>26 Apr 2006 10:06:53 451 Timeout waiting for client input

For reasons of efficiency, LISTSERV's outgoing SMTPWorkers (smtpw.exe) try
to keep the connection to the outbound SMTP server open all the time, rather
than open the socket, send one piece of mail, close the socket.  As such,
the SMTPWorkers are not aware that the outbound SMTP server has in fact
closed the socket after its timeout period.  

When there is new mail to send SMTPW trys, but gets the [10053]
(WSAECONNABORTED) error.  It then opens and new socket and sends the mail.

Your log is typical for a low-med traffic server where this is not a
constant flow of outgoing mail.

Reference for the 10053 error (and other TCP Socket errors)

  http://www.sockets.com/a_c.htm