Re: Blocking SMTP Port 25

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

From: Jeff L (newsgroupsremoveandunderscore_jeff_at_availabletech.net)
Date: 06/30/04 

Date: Tue, 29 Jun 2004 21:41:26 -0400

Lanwench, Sorry about the previous misspelling of your handle.

You are right. The original post does say "outbound from the network". We
try prevention rather than fire fighting. Jon, you might want to look into
attachment blocking using ISA.

Regards,

Jeff

"Lanwench [MVP - Exchange]"
<lanwench@heybuddy.donotsendme.unsolicitedmail.atyahoo.com> wrote in message
news:uRMdYujXEHA.3120@TK2MSFTNGP12.phx.gbl...
> Jeff L wrote:
> > Lanwrench,
> >
> > Are you saying that he should be blocking relays through ISA. I
> > agree. Are you suspecting he is an open relay?
> >
> > Most of the virus attacks we are blocking coming in on Port 25 are
> > wrapped in emails coming from spammers. We deny connections from
> > known spammers in order to cut down on viruses and still receive
> > email from legitimate sources. This is done through Exchange, do you
> > agree?
>
> Yes - and Exchange 2003 is not an open relay by default (altho' everyone
> ought to disable authenticated relay, too, unless absolutely necessary &
> only leave it enabled *if* complex passwords are used w/regular pw changes
&
> guest is left disabled). It was my understanding from the original post
that
> they wanted to prevent any outbound SMTP traffic on their network from any
> box other than their Exchange server.
> >
> > Jeff Loucks
> > Available Technology ®
> > Solutions For Professionals ®
> > www.availabletechnology.com
> >
> >
> > "Lanwench [MVP - Exchange]"
> > <lanwench@heybuddy.donotsendme.unsolicitedmail.atyahoo.com> wrote in
> > message news:OG$ziJjXEHA.3596@tk2msftngp13.phx.gbl...
> >> Your firewall or ISA server is where you need to set this....
> >>
> >> Jon R wrote:
> >>> Hi, I'm looking to block port 25 for outgoing traffic which doesnt
> >>> originate from the SBS 2000 server. Can anyone point me in the right
> >>> direction on this?
> >>>
> >>> Thanks
>
>

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