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Maybe someone could explain how to use Telnet to test Virtual SMTP Server on another machine with Windows 2008?

I have tried command below and get unrecognized command error. (The actual server deomain replaced with xxxxx)

Telnet smtp.xxxxx.com 25
220 xxxxx.com Microsoft ESMTP MAIL Service, Version: 7.0.6002.18222 rea
dy at  Tue, 23 Oct 2012 15:57:18 +0300
FROM: tomas@MyDomain.com
500 5.3.3 Unrecognized command
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1 Answer 1

up vote 5 down vote accepted

Your syntex needs to start with helo dominaname.com. Example below. Make sure to use enter spaces correct and the period at the end.

    telnet xxx.domainname.com 25
    helo domainname.com
    mail from: myaddress@domain.com 
    rcpt to:youraddress@domain.com 

    to: myaddress@domain.com
    from: myaddress@domain.com    
    Subject:This is a test



If your lazy just use http://mxtoolbox.com/diagnostic.aspx

Assuming its a external server.

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