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@iharosi
Created March 8, 2017 09:59
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How to test SMTP operations using Telnet
1. Telnet into Exchange server hosting IMS service using TCP port 25.
Command is telnet <servername> 25
2. Turn on local echo on your telnet client so that you can see what you are typing.
On Win 9x and NT 3.5/4.0 Telnet client this done by selecting the "preferences" from the "terminal" pull down menu, and checking the local echo radio button. For Windows 2000 telnet client, issue command "set local_echo", from the telnet command prompt.
3. Issue the following smtp command sequence
helo <your domain name><enter>
response should be as follows
250 OK
mail from: <your Email Address><enter>
response should be as follows
250 OK - mail from <your Email address>
rcpt to: <recipient address><enter>
response should be as follows
250 OK - Recipient <recipient address>
data<enter>
response should be as follows
354 Send data. End with CRLF.CRLF
To: <recipient's display name><enter>
From: <your display name><enter>
Subject: <Subject field of Email message><enter>
<Enter you body text><enter><enter> . <enter>
response should be as follows
250 OK
quit<enter>
from http://exchange.mvps.org/smtp_frames.htm
http://www.cyberciti.biz/tips/howto-postfix-masquerade-change-email-mail-address.html
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