Using telnet

The telnet application is a handy means of testing SMTP relay server connectivity and your user authentication.

To get started –
1. Ensure telnet is installed/enabled on your PC (assuming you’re using Windows).
2. Get the Base64 encoded values of your username and password (base64encode.org)
3. Have a TO and FROM address ready to go

You can use the following ports: 25, 587, 2525, and for secure sending, 465. From a command prompt (using port 2525 as an example), enter the command below, and a new page will appear where you will enter your encoded login, password, FROM address, TO address, a subject line as shown or use your own wording for the subject, enter some text like “hello,” hit the enter key to generate a blank line, and end the message/connection by entering a single period/enter.

telnet express-relay.jangosmtp.net 2525

220 express-relay.jangosmtp.net ESMTP Welcome to the JangoSMTP trackable email relay system.
ehlo express-relay.jangosmtp.net
250-express-relay.jangosmtp.net Hello 66-192-xxx-xxx.static.twtelecom.net [66.192.xxx.xxx], Haraka is at your service.
250-PIPELINING
250-8BITMIME
250-SIZE 31457280
250-STARTTLS
250 AUTH PLAIN LOGIN
auth login
334 VXNlcm5hbWU6
enter your Base64 encoded username
334 UGFzc3dvcmQ6
enter your Base64 encoded password
235 Authentication successful
mail from:enter your valid FROM address
250 sender  OK
rcpt to:enter your_recipient@wherever.com here
250 recipient  OK
data
354 go ahead, make my day
subject:testing express-relay
hello

.
250 Message Queued (4FEFB870-379A-45ED-A76C-B474AB3F6E71.1)
quit
221 express-relay.jangosmtp.net closing connection. Have a jolly good day.