RE: How to prevent unauthorized use of my SMTP server?

  • From: "Mark Fugatt" <markfu@xxxxxxxxxxxxx>
  • To: "[ExchangeList]" <exchangelist@xxxxxxxxxxxxx>
  • Date: Mon, 8 Aug 2005 20:50:41 +0100

By default Exchange 2000 and Exchange 2003 do not allow unauthorised
relaying, this article explain how to check:

Mark Fugatt 
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-----Original Message-----
From: Nicolas Verhaeghe [mailto:nicolas@xxxxxxxxxxxxxxxxxxx] 
Sent: 08 August 2005 18:45
To: [ExchangeList]
Subject: [exchangelist] How to prevent unauthorized use of my SMTP

How do I make sure that my SMTP server is not open to the rest of the

It seems that I need to have port 25 opened in my firewall to allow
incoming mail, but when I do that, don't I risk letting outsiders use my
SMTP to send their spam?

How can I monitor this activity and also how can I make sure that no
non-authenticated users use my Exchange server?

Thanks a lot!

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