Quick way to verify SMTP server

Source From: http://www.garnetchaney.com/how_to_telnet_to_a_mail_server.shtml

SMTP - To Send Mail

To send mail:

1. Bring up telnet
2. Type "open (your mail server here) 25"
3. This will connect to your mail server on port 25 (the smtp port) SMTP stands for Simple Mail Transfer Protocol.
4. Type "HELO (site you want the mail server to record you connecting from...this can be anything you want)" Some mail servers do not require this line.
5. If you want the mail server/receiver of the email to know who this email is from type "MAIL FROM: yourname@whereever.com (replace this with whatever you want)" **Note: Some mail servers require this line...if you get an error that blank sender is not allowed than use this command.
6. To tell the mail server where you want your mail to go to type "RCPT TO: (where you want the mail to go)". **Warning: If you incorrectly enter the destination of the mail it will be sent to the postmaster of the receiving server (usually the mail server will give you an error informing you that the user does not exist and that this message will be sent to the postmaster).
7. Then type "DATA"
8. The mail server will give you specific instructions on how to terminate the message (usually a "." on a line by itself) you must use this or else you will not be able to send the message!
9. Type your message
10. Then terminate the message with the appropriate character
11. At this point you generally type "QUIT" to disconnect as your message is sent.