C# Sending email using eircom.net

beanian

Hi,
I have been getting the following error when trying to send an email using c# and the eircom.net server. I have turned off any firewalls and tried using ssl but that hasnt helped.
Error:
Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.

Here is my code..

SmtpClient client = new SmtpClient();
client.Credentials = new NetworkCredential("xxx@eircom.net", "password");

client.Host = "mail1.eircom.net";
//client.EnableSsl = true;
client.Port = 25;
client.Send(email);

Any suggestions would be great.
Thanks
Ian

outofcoolnames

Set objEmail = CreateObject("CDO.Message")

objEmail.From = "sample@eircom.net" '<<<<<<

---

Enter Your.Name again here and
objEmail.To = "destination@eircom.net" 'capitilize first letter of each name.
objEmail.Subject = "test email"
objEmail.Textbody = ""
objEmail.Configuration.Fields.Item _
("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2
objEmail.Configuration.Fields.Item _
("http://schemas.microsoft.com/cdo/configuration/smtpserver") = _
"mail1.eircom.net"
objEmail.Configuration.Fields.Item _
("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = 25
objEmail.Configuration.Fields.Update
objEmail.Send

ressem

Well the code is OK, assuming you're using a network connection/ ethernet modem to connect to the internet.
Does the "from" value in the message match the user name?
Usually there is a restriction to prevent spamming.

Using SSL won't help in debugging.
I'd suggest running Ethereal/Wireshark www.wireshark.org on your computer if possible to examine the SMTP transaction to find out exactly where the problem occurs.

A typical transaction will go like
220 mailserver.eircom.net ready
EHLO myhostname
250-mailserver.eircom.net Hello [yourmachine]
250-HELP
250-ETRN
250-DSN
250-AUTH LOGIN
250 AUTH=LOGIN
AUTH login abcdefg
334 fakehashwxfxr3
fakepasswordhash43rf4x
235 LOGIN authentication successful
MAIL FROM:<me@eircom.net
250 OK - mail from <me@eircom.net>
RCPT TO:<destination@example.com>
250 OK - Recipient <destination@example.com>
DATA
354 Send data. End with CRLF.CRLF
mime-version: 1.0
from: me@eircom.net
to: destination@example.com
date: 20 Sep 2006 13:31:11 +0100
subject: Test mail
content-type: text/plain; charset=us-ascii
content-transfer-encoding: quoted-printable
Mail body
.
250 OK

Where the numbers preceding lines indicate that the line was sent by the server, and it's success/fail state.
Stuff in italics was sent by the .net smtp client