Re: Non-Existing addresses

Are you running any kind of spam filter gateway in front of your Exchange
server? or is your Exchange server having to deal with it all?
If you are running some kind of filter gateway, check it to see if they have
a way of dealing with it.

We are running the SurfControl E-mail filter in an SMTP Gateway
configuration with the Surfcontrol machine in the DMZ and the Exchange
Server totally behind the firewall. I use a small server with dual
processors, but doesn't require any significant data storage, that is the
recipient of mail (MX record points to this machine). It blocks mail using
DNS RBL servers to drop e-mail from known spammers, then it does an LDAP
lookup on our Domain Controller to check for existing accounts. If the
address does not exist on our system, the E-mail Filter machine sends the
NDR report back. Then there are spam rules that eliminate more spam.

The RBL check with the LDAP lookup is eliminating 75-80% of the attempted
deliveries and the spam rules are quarantining 50% of what is left; all
before anything hits the Exchange Server.

By doing the LDAP lookup from the Spam filter machine, you keep the NDRs
flowing for those individuals who can't enter addresses correctly, but
really take a big load off the Exchange server.

Take care.

Bob

"Joe Williams" <Joe@xxxxxxxxxxxx> wrote in message
news:u7qfhc$oFHA.2472@xxxxxxxxxxxxxxxxxxxxxxx
> Is there an easy way to configure exchange to drop all mail that does not
> have a valid e-mail address? WE get thousands of e-mails that are just
> spam blasts to no one in particular and the server generates NDR after
> NDR.
>
> I would like to eliminate Exchange from having to even deal with these
> messages by just dropping it if it is a non-existent address.
>
> I know that this might be a hassle if someone accidentally types a wrong
> address for a real e-mail, but when your inibound mail is 80% spam you
> gotta do something!
>
> Thoughts?
>
> THanks
>
> Joe
>


.

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