Send mail with telnet over SMTP

How to test your SMTP server? Use telnet. Open up a command prompt and telnet to your smtp server: TELNET server 25, where 25 is the default SMTP port.

220 ...
HELO [your name, can be anything]250 ...
MAIL from: [your email address, can be anything]250 ... Sender OK
RCPT to: [destination email address]250 ...
RCPT to: [destination email address]
250 ...
DATA
[type the message body including mail headers, end with enter . enter]250 Queued mail for delivery

The bold italic lines are the lines you have to type. Note, telnet sends every character you type directly to the server, so typo's are not allowed! I also a program called TCP, that does the same as telnet but only sends data after a return, so you can use that backspace!