I need help with Exchange 2003 Authentication through Telnet

25 pts.
Email authentication
Exchange 2003 authentication
Microsoft Exchange 2003
Unified Messaging
I'm having trouble getting email to authenticate correctly using Telnet. I can get email using Outlook, OWA, and Sync is working too for mobile phones. The company is going to integrate Unified Messaging using a NEC product. The NEC product needs to be able to login through telnet. When I telnet to the exchange server to make sure that the account I setup for the UC is working correctly. I get the below read out from telnet. I tried other user accounts too and the same issues arise. 220 servername Microsoft ESMTP MAIL Service, Version: 6.0.3790.3959 ready at Thu, 18 Dec 2008 13:22:41 -0500 ehlo 250-servername Hello [] 250-TURN 250-SIZE 250-ETRN 250-PIPELINING 250-DSN 250-ENHANCEDSTATUSCODES 250-8bitmime 250-BINARYMIME 250-CHUNKING 250-VRFY 250-X-EXPS GSSAPI NTLM 250-AUTH GSSAPI NTLM 250-X-LINK2STATE 250-XEXCH50 250 OK mail from: user@domain.com 454 5.7.3 Client does not have permission to submit mail to this server. Connection to host lost. Press any key to continue...

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Open Telnet (Start – Run – CMD – Telnet) and write the following line:

TELNET Servername.Domain.TLD 110 (in our example TELNET London.nwtraders.msft 110).

– The Exchange Server accepts Connection to Port 110

Exchange Server 2003 POP3 – It is a Exchange 2003 Server

Version 6.5.7226.0 – The Exchange Version Number

London.nwtraders.msft – The FQDN of the Exchange Server

These are some helpful information about our connection.

Let’s go further:

What do we see here?

USER MSEXchangeORG – The name of the user to connect to the mailbox

PASS Fake001 – The password of the user (transmitted unencrypted over the network)

LIST – Lists all E-Mails in the mailbox

RETR 1 – Display the selected E-Mail

A very interesting part is the displayed body of the E-Mail. You can see the encapsulation of the E-Mail, MIME type, Message ID and much more helpful information.

POP commands


The User you would like to connect to


The password of the user (transmitted unencrypted over the network)


Overview over the POP3 mailbox


Displays every message in listform


Displays selected message (RETR 1)


Deletes selected message (DELE 1)


NO Operation


Undo DELE function


End POP3 Session
Connecting to SMTP

Open Telnet (Start – Run – CMD – Telnet) and write the following line:

TELNET Servername.Domain.TLD 25 (in our example TELNET London.nwtraders.msft 25).

SMTP supports two verbs: HELO an EHLO

The HELO or EHLO verbs in SMTP are how the client identifies itself to the server. Clients that use single-label domain names, or domain names that the server cannot look up in the DNS database, are broken or misconfigured.

EHLO is the successor of the HELO verb and supports many more commands. The supported EHLO verbs are different from Mailserver to Mailserver. Exchange 2003 supports the EHLO verbs .

A very important EHLO verb is AUTH. AUTH lists the supported authentication methods for connecting to the SMTP Server. Exchange 2003 supports GSSAPI, NTLM and LOGIN.

Some ISP SMTP servers doesn’t support AUTH. They use SMTP after POP. SMTP after POP authenticates a user through a successful POP3 connection and lets him use the SMTP protocol with the applied credentials through the POP3 connect.

In our example we use the basic HELO command to connect.

What do we see here?

220 London.nwtraders.msft – the Server listens on the given SMTP port

Microsoft ESMTP Mail Service – This Server supports Extended SMTP

Version: 6.0.3790.0 ready – This SMTP Service is hosted by Windows 2003

HELO – Initiates connection (requires domain name by most SMTP


250 London.nwtraders.msft – Server accepts connections on IP address

MAIL FROM: Name@domain.tld – The Sender of the Message

RCPT TO: Name@domain.tld – The Reciepient of the Message

DATA: – Input e-mail data for subject and body

SUBJECT: – the subject line of the message

Enter the data for the message body. At the end of the message click <CRLF> “.” <CRLF>

The message will be transmitted through the destination address through exchange.

SMTP commands


Identifies the Client


Specifies Mail Sender


The Reciepient of the message


The Data part of the message


Resets message transmiting


Verifies e-mail address


Expand a mailing list


Delivery Status Notification


Displays help


NO Operation




Extended TURN


Verbose Mode


End SMTP Session

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