Send Email Using Telnet

Open the cmd prompt . To open the command window, go to Start-> Run. Or press win key + R, type "cmd," and click OK.

Ping the server. Type "telnet mail.server.com 25" where "mail.server.com" is the name of the smtp server of your email provider (such as smtp-server.austin.rr.com) and 25 is the port number used by the SMTP service. (This number can be found by checking your account info in the program you normally use for email.) After you enter the above command you should receive a reply like "Trying xxx.xxx.xxx, Connected to mail.server.com".

Specify the domain you're using to send mail. To specify the domain, type in the below command:

• HELO local.domain.com (use your fully qualified domain name here).
• You should receive a reply like: "250 mail.server.com Hello local.domain.name pleased to meet you".

Enter your email address. Enter a space after the colon (:), and enter your email address as follows:

• MAIL FROM: yourname@domin.com
• This should give you a message ending with "250 ...Sender OK". 

Enter the email address of the recipient. Type in the below command:

• RCPT TO: friend@otherdomain.com
• Note that you can enter more addresses if you intend to email more than one person.
• You should see a message ending with "250 ...Recipient OK".

Compose your message. To start writing, type DATA and press Enter.

• On the next line, type "SUBJECT: [your subject here]" and press Enter twice.
• Continue typing your message.
• To end your message, put a single period (.) on a line by itself, and press Enter.
• You should see something saying "Message accepted for delivery."

Exit telnet. Type QUIT to exit.

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