the SMTP Relay is locked down to specific IP Addresses, but my situation is that I was able to use a valid email addresses witin the organization from outside the firewall without having to provide a user name and a password. Thanks -----Original Message----- From: Carl Houseman [mailto:c.houseman@xxxxxxxxx] Sent: Sunday, January 15, 2006 9:34 PM To: [ExchangeList] Subject: [exchangelist] RE: Using SMTP Engine from outside the network http://www.MSExchange.org/ It may or may not be "normal" (i.e. "default") depending on your version of Exchange. The feature you have left enabled (Exchange 5.5) or accidentally enabled (Exchange 200x) is called "relay". Information on turning it off: http://www.google.com/search?hl=en&q=exchange+relay If the above isn't sufficient, then identify your version of Exchange for more specific instruction. You might also check to see if your mail system's outside IP address has been blacklisted. If so, it means your mail system has been used for sending spam. http://www.dnsstuff.com/ Use "Spam database lookup" Even permitting relay just to authorized users is hazardous and can leave your mail system open to abuse from unauthorized parties, unless you ensure that authorized relayers have very strong passwords. -----Original Message----- From: Bryan [mailto:mjtech@xxxxxxxxx] Sent: Sunday, January 15, 2006 9:10 PM To: [ExchangeList] Subject: [exchangelist] Using SMTP Engine from outside the network Hi all, I was working on a batch file to make it run ipconfig /all create a text file with the result and email it to me. While working on it I discovered that I was able to use our SMTP engine from outside without any authentication, like this: commail.exe -host=ServerName.DomainName.com -from=MyEmail1@xxxxxxxxxxxxxxx -to=MyEmail2@xxxxxxxxxxxxxxx Is this normal? How can I secure it so it would only be used by authorized personels. Thanks ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp ------------------------------------------------------ Visit TechGenix.com for more information about our other sites: http://www.techgenix.com ------------------------------------------------------ You are currently subscribed to this MSExchange.org Discussion List as: mjtech@xxxxxxxxx To unsubscribe visit http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Report abuse to info@xxxxxxxxxxxxxx