Right, here's a log of a simple email using telnet. Remember that this is an example, emails will be taken out.
Open nslookup --> set type=mx --> gmail.com
Take a smtp address, like gmail-smtp-in.l.google.com
Open Telnet, o gmail-smtp-in.l.google.com 25, opens a connection to gmail-smtp-in.l.google.com on port 25 (SMTP).
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220 mx.gmail.com ESMTP 28si266586wrl
helo world
250 mx.gmail.com at your service
ehlo
250-mx.gmail.com at your service
250-SIZE 20971520
250-8BITMIME
250 ENHANCEDSTATUSCODES
mail from: <example@blehster.bleh>
250 2.1.0 OK
rcpt to: <GMAIL-USERNAME-GOES-HERE@gmail.com>
250 2.1.5 OK
data
354 Go ahead
Subject: Test
This is a test. Making mistakes will appear.
Bleh
.
250 2.0.0 OK 1125092386 28si266586wrl
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for some reason the server won't work unless you do ehlo as well. remember when ending an email to do enter dot enter so it knows to send it. Use quit to quit from the server.
=]