smtp send mail fail using postfix in Linux

Question

I try to use postfix smtp service to send email in Linux.
but it return fail message**(Delivery has failed to these recipients or groups:)**

i follow this article to setup my postfix.
http://www.daliycode.com/info-3-201.html

I found my exchange server only support ntlm auth.

so I try to use telnet to auth and send email. but it alos fail.

telnet mail_server_domain 25
EHLO mail_server_domain
AUTH NTLM
base64_my_email
base64_password
535 5.7.3 Authentication unsuccessful

it return "535 5.7.3 Authentication unsuccessful" message.
so anybody know this issue?

Answer 1

Why the need to authenticate to Exchange? Why not just send the message anonymously?

Answer 2

@nang
Hi,

Agree with Andy,there is no need to authenticate.
In your case, you may create a dedicated receive connector on your Exchange server and only allow your linux server to relay messages.
You can find the detailed steps in this document: Allow anonymous relay on Exchange servers

As long as you specific the ip addresses or ip address range that are allowed to use the receive connector, your Exchange server won't be used as a open relay.

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