SMTP Outgoing - Connection Dropped

Hi

I have the same problem that was listed by teksysman on the 07/25/2005 "The
coonection was dropped by the remote host". This only occurs with certain
domain names and never with others. I can send a successful email using
Telnet to any of the domains that are giving me grief.

I have directed my ISP to direct everything to do with our domain
'des.com.au' to our site.

This has been a 6 week battle and I am not winning! Help, Please!

Included below is Server Log of Email through Exchange, then with Telnet,
and then SMTPDiag. I apologise for the length of this email, but thought it
better to include the data.

The Server Log File records the following when sending email from
brett@xxxxxxxxxx to carolmundy@xxxxxxxxxxxxxxxxxx
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionResponse SMTPSVC1 SLAVE
- 25 - - 220+secmx1.sa.chariot.net.au+ESMTP+Postfix 0 0 42 0 32 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionCommand SMTPSVC1 SLAVE -
25 EHLO - des.com.au 0 0 4 0 32 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionResponse SMTPSVC1 SLAVE
- 25 - - 250-secmx1.sa.chariot.net.au 0 0 28 0 63 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionCommand SMTPSVC1 SLAVE -
25 MAIL - FROM:<brett@xxxxxxxxxx>+SIZE=1497 0 0 4 0 63 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionResponse SMTPSVC1 SLAVE
- 25 - - 250+Ok 0 0 6 0 110 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionCommand SMTPSVC1 SLAVE -
25 RCPT - TO:<carolmundy@xxxxxxxxxxxxxxxxxx> 0 0 4 0 110 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionResponse SMTPSVC1 SLAVE
- 25 - - 250+Ok 0 0 6 0 500 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionCommand SMTPSVC1 SLAVE -
25 DATA - - 0 0 4 0 500 SMTP - - - -
2005-08-02 20:30:53 203.87.93.130 OutboundConnectionResponse SMTPSVC1 SLAVE
- 25 - - 354+End+data+with+<CR><LF>.<CR><LF> 0 0 35 0 532 SMTP - - - -

The following works from the command prompt on the server.
TELNET secmx1.vic.chariot.net.au 25
220 secmx1.vic.chariot.net.au ESMTP Postfix
EHLO des.com.au
250-secmx1.vic.chariot.net.au
250-PIPELINING
250-SIZE 18000000
250-ETRN
250 8BITMIME
MAIL FROM:brett@xxxxxxxxxx
250 Ok
RCPT TO:carolmundy@xxxxxxxxxxxxxxxxxx
250 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
Subject: Test

Oh for a glass of scotch!
..
250 Ok: queued as 6E9AF3D2450
QUIT
221 Bye
Connection to host lost.
C:\>

SMTPDiag shows the following...

C:\>cd \clientapps\smtpdiag

C:\ClientApps\SmtpDiag>smtpdiag brett@xxxxxxxxxxx
carolmundy@xxxxxxxxxxxxxxxxxx
/v

Searching for Exchange external DNS settings.
Computer name is SLAVE.
VSI 1 has the following external DNS servers:
139.130.4.4,203.50.2.71

Checking SOA for dessminibus.com.au.
Checking external DNS servers.

Checking TCP/UDP SOA serial number using DNS server [139.130.4.4].
TCP test failed.
UDP test succeeded.
Serial number: 2005030201

Checking TCP/UDP SOA serial number using DNS server [203.50.2.71].
TCP test failed.
UDP test succeeded.
Serial number: 2005030201
Checking internal DNS servers.

Checking TCP/UDP SOA serial number using DNS server [192.168.1.45].
TCP test succeeded.
UDP test succeeded.
Serial number: 2005030201
SOA serial number match: Passed.

Checking local domain records.
Starting TCP and UDP DNS queries for the local domain. This test will try to
validate that DNS is set up correctly for inbound mail. This test can fail for
3 reasons.
1) Local domain is not set up in DNS. Inbound mail cannot be routed to
local mailboxes.
2) Firewall blocks TCP/UDP DNS queries. This will not affect inbound mail,
but will affect outbound mail.
3) Internal DNS is unaware of external DNS settings. This is a valid
configuration for certain topologies.
Checking MX records using TCP: dess.com.au.
MX: mail.webclick.com.au (10)
Checking MX records using UDP: dess.com.au.
MX: mail.webclick.com.au (10)
A: mail.webclick.com.au [203.217.15.3]
Both TCP and UDP queries succeeded. Local DNS test passed.

Checking remote domain records.
Starting TCP and UDP DNS queries for the remote domain. This test will try to
validate that DNS is set up correctly for outbound mail. This test can fail
for
3 reasons.
1) Firewall blocks TCP/UDP queries which will block outbound mail. Windows
2000/NT Server requires TCP DNS queries. Windows Server 2003 will use UDP
queries first, then fall back to TCP queries.
2) Internal DNS does not know how to query external domains. You must
either use an external DNS server or configure DNS server to query external
domains.
3) Remote domain does not exist. Failure is expected.
Checking MX records using TCP: dessminibus.com.au.
MX: mail.dessminibus.com.au (10)
MX: secmx.sa.chariot.net.au (20)
MX: secmx.vic.chariot.net.au (30)
A: secmx.sa.chariot.net.au [203.87.93.132]
A: secmx.sa.chariot.net.au [203.87.93.130]
A: secmx.sa.chariot.net.au [203.87.93.131]
A: secmx.vic.chariot.net.au [203.87.5.165]
A: secmx.vic.chariot.net.au [203.87.5.164]
A: mail.dessminibus.com.au [203.87.94.242]
Checking MX records using UDP: dessminibus.com.au.
MX: mail.dessminibus.com.au (10)
MX: secmx.sa.chariot.net.au (20)
MX: secmx.vic.chariot.net.au (30)
Both TCP and UDP queries succeeded. Remote DNS test passed.

Checking MX servers listed for carolmundy@xxxxxxxxxxxxxxxxxxx
Connecting to mail.dessminibus.com.au [203.87.94.242] on port 25.
Received:
220 apollo.picknowl.com.au ESMTP Postfix

Sent:
ehlo dess.com.au

Received:
250-apollo.picknowl.com.au
250-PIPELINING
250-SIZE 20480000
250-VRFY
250-ETRN
250 8BITMIME


Sent:
mail from: <brett@xxxxxxxxxxx>

Received:
250 Ok

Sent:
rcpt to: <carolmundy@xxxxxxxxxxxxxxxxxx>

Received:
250 Ok

Sent:
quit

Received:
221 Bye

Successfully connected to mail.dessminibus.com.au.
Connecting to secmx.sa.chariot.net.au [203.87.93.131] on port 25.
Received:
220 secmx2.sa.chariot.net.au ESMTP Postfix

Sent:
ehlo dess.com.au

Received:
250-secmx2.sa.chariot.net.au
250-PIPELINING
250-SIZE 18000000
250-ETRN
250 8BITMIME


Sent:
mail from: <brett@xxxxxxxxxxx>

Received:
250 Ok

Sent:
rcpt to: <carolmundy@xxxxxxxxxxxxxxxxxx>

Received:
250 Ok

Sent:
quit

Received:
221 Bye

Successfully connected to secmx.sa.chariot.net.au.
Connecting to secmx.sa.chariot.net.au [203.87.93.130] on port 25.
Received:
220 secmx1.sa.chariot.net.au ESMTP Postfix

Sent:
ehlo dess.com.au

Received:
250-secmx1.sa.chariot.net.au
250-PIPELINING
250-SIZE 18000000
250-ETRN
250 8BITMIME


Sent:
mail from: <brett@xxxxxxxxxxx>

Received:
250 Ok

Sent:
rcpt to: <carolmundy@xxxxxxxxxxxxxxxxxx>

Received:
250 Ok

Sent:
quit

Received:
221 Bye

Successfully connected to secmx.sa.chariot.net.au.
Connecting to secmx.sa.chariot.net.au [203.87.93.132] on port 25.
Received:
220 secmx3.sa.chariot.net.au ESMTP Postfix

Sent:
ehlo dess.com.au

Received:
250-secmx3.sa.chariot.net.au
250-PIPELINING
250-SIZE 18000000
250-ETRN
250 8BITMIME


Sent:
mail from: <brett@xxxxxxxxxxx>

Received:
250 Ok

Sent:
rcpt to: <carolmundy@xxxxxxxxxxxxxxxxxx>

Received:
250 Ok

Sent:
quit

Received:
221 Bye

Successfully connected to secmx.sa.chariot.net.au.
Connecting to secmx.vic.chariot.net.au [203.87.5.164] on port 25.
Received:
220 secmx1.vic.chariot.net.au ESMTP Postfix

Sent:
ehlo dess.com.au

Received:
250-secmx1.vic.chariot.net.au
250-PIPELINING
250-SIZE 18000000
250-ETRN
250 8BITMIME


Sent:
mail from: <brett@xxxxxxxxxxx>

Received:
250 Ok

Sent:
rcpt to: <carolmundy@xxxxxxxxxxxxxxxxxx>

Received:
250 Ok

Sent:
quit

Received:
221 Bye

Successfully connected to secmx.vic.chariot.net.au.
Connecting to secmx.vic.chariot.net.au [203.87.5.165] on port 25.
Received:
220 secmx2.vic.chariot.net.au ESMTP Postfix

Sent:
ehlo dess.com.au

Received:
250-secmx2.vic.chariot.net.au
250-PIPELINING
250-SIZE 18000000
250-ETRN
250 8BITMIME


Sent:
mail from: <brett@xxxxxxxxxxx>

Received:
250 Ok

Sent:
rcpt to: <carolmundy@xxxxxxxxxxxxxxxxxx>

Received:
250 Ok

Sent:
quit

Received:
221 Bye

Successfully connected to secmx.vic.chariot.net.au.

C:\ClientApps\SmtpDiag>



>From Brett


.

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