Test SMTP through Telnet

Sometimes you need a tool to verify if SMTP is enabled and if it is able to relay messages.  Telnet is great for that.  Also Putty is a great Telnet client.

Below are the steps to send a mail using telnet or Putty.

You do/type this	Server responds with
Telnet to hostname on port 25	220 (then identifies itself - possibly with several lines of 220 + text)
HELO your_domain_name or whatever	250 (followed by human readable message)
MAIL FROM:you@hostname.com (ie, your email address)	250 is syntactically correct (or similar)
RCPT TO:them@someplace_else.com (email address you want to send to)	250 is syntactically correct
DATA	Tells you to send data then CRLF period CRLF at end
You type your message then CRLF period CRLF (ie, type a period on a line by itself then hit ENTER)	250
QUIT	Signoff message