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IMC accepts Mail%domain.com address 1

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jrmjh

Technical User
Oct 8, 2002
30
US
Does any one know how to configure Exchange 5.5 IMC to "550" when an address is sent in the user%domain.com format. My server currently "250 OK"s the address then send a non delivery report. I have been told that Open relay testers see this as possible relay hosts because it does not conform to RFC.
 
Check out the FAQ on relaying in this forum.

Don't forget to give it 10/10 vote...
 
I have set up according to FAQ and other guides. But Telnet to port 25 and sending "RCPT TO: user%domain.com" results in "250 OK" reply still.
 
A source-routed address is an email address which gateways through another host. For example, the address "john%somewhere.com@elsewhere.com" is actually "john@somewhere.com", but it first gets delivered to "elsewhere.com", which then forwards the mail on to "somewhere.com".

Source routed address are legitimate according to Internet standards, but their use is "deprecated" (i.e., discouraged) by the standards.

Some older networks still use source-routed addresses (for example, BITNET), but most do not. In 1997, AOL banned all source-routed email from their network, so that most remaining source-routed sites upgraded their sites to not use source routing.

It is not clear how effective banning source-routed email is in getting rid of junk mail, but since AOL did it, MailShield provides the option as well.


Dev
 
I have a firewall that allows me to not accept the % or some of the other source routed addresses. Turning off routing by itself in Exchange will not turn off all relaying. Source routed addresses can still be relayed off of your server. I did a ton of research to first stop relaying, then learned about source routing, then blocked that through our firewall.

Dev
 
Which firewall product are you using?
 
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