Matthew Byng-Maddick said:
> deny all yahoo.* messages where the HELO (which must contain .yahoo.) does
> not resolve to the IP address of the peer SMTP.
>
> That will cut down a fair amount
The problem with that is that you will then reject legit email.
Example: A seller on Ebay will use a free account like yahoo, msn,
hotmail as their mail address, but will send mail via Ebay's mail system.
Now are you going to reject a message because it came from Ebay but has a
Yahoo address?? If you do, how are you going to communicate with them?
However, if the incoming message does a HELO with yahoo.com or any of the
others and the host is not a yahoo.com or respective host, they are just
plain lying about the connection, and stopping those will stop a lot of
spam.
Other spam rules will catch most of the other.
Just denying all yahoo, msn, hotmail etc... is lose you real email...
A lot of people use the free accounts as a way to defeat them from getting
spam. They switch accounts when the spam level gets too high.
--
Kevin W. Reed - TNET Services, Inc.
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