Testing SMTP Server from the windows command line

C:\Users\Administrator>telnet relay.mx.testserver.com 25

220 mb1relay1.mx.testserver.com ESMTP
helo test
250 mb1relay1.mx.testserver.com
mail from: usename1@mail.com
250 sender <usename1@mail.com> ok
rcpt to: usename2@mail.com
250 recipient <usename2@mail.com> ok
data
354 go ahead
Hi How are you
.
250 ok:  Message 258249 accepted
quit
221 mb1relay1.mx.testserver.com


Connection to host lost.

Ref :- https://www.youtube.com/watch?v=lfYtz3uRPYc