Re: Getting Relayed and can't stop it. Please help.

Tech-Archive recommends: Speed Up your PC by fixing your registry

From: Lanwench [MVP - Exchange] (lanwench_at_heybuddy.donotsendme.unsolicitedmail.atyahoo.com)
Date: 04/13/04 

Date: Mon, 12 Apr 2004 20:21:04 -0400

Have them authenticate to your SMTP server or use their ISP's SMTP server
until you migrate them off POP - then you can close your open relay. This
would be a Very Good Thing.

You may still get hit with 'authenticated relay' spam, note - unless you've
got a very good password policy (complex passwords, regular changes,
renaming default/built-in accounts, leaving guest disabled). So if you can
have them use their ISP's SMTP server, do it...then disable authenticated
relay as well.

However - the NDRs may be unrelated - a lot of viruses spoof the sender, as
does a lot of spam. So the 'purported' sender gets the NDR.

Mikek wrote:
> Hello,
> Running 5.5, sp4 on NT 4.0 sp6a. I have 300 users with 50 of them
> being POP (we are converting them to full server side mail) using
> Outlook 2K and 2002.
> Getting lots of complaints from users who state they're getting NDR's
> with their address from users they know nothing about. I have about
> 100 messages in the IMC queue each morning with the typical <> that I
> just delete. Routing tab is set to route to internal domain (works
> fine). Under routing restrictions, nothing is checked at this time.
> I was told if I check 'Hosts and clients that successfully
> authenicate', this would cause issues with my POP users. Do I have
> any other options ?? Any advice would be greatly appreciated so
> thanks for ANY help. This all started about 2 weeks ago.
>
> thanks,
> Mike

Relevant Pages

  • Re: Locking Virtual SMTP server
    ... Yes fritz I know pop3 is a protocol only to be able to ... smtp server in order to be able to relay thru it. ... My relay settings stand as this. ... Allow all computers which successfully authenticate to relay regardless ...
    (microsoft.public.exchange.admin)
  • Re: Confused about POP3, SMTP and Authentication
    ... You have to set up the clients to authenticate to the SMTP server. ... this is not the best setup anyway....and leaving auth relay ... remote users can use Outlook or OE to retrieve their emails. ...
    (microsoft.public.exchange.admin)
  • Re: Confused about POP3, SMTP and Authentication
    ... You have to set up the clients to authenticate to the SMTP server. ... this is not the best setup anyway....and leaving auth relay ... remote users can use Outlook or OE to retrieve their emails. ...
    (microsoft.public.exchange.admin)
  • Re: spam sent through our server using postmaster@
    ... Bill Lucas wrote: ... I don't think so...not sure as I don't allow POP or relay. ... > think that would be perfect since no one can authenticate via POP, ... users to use their own ISP's SMTP server? ...
    (microsoft.public.exchange2000.admin)
  • Re: SMTP Exchange 2k relay authentication
    ... > NB THERE IS NO USERNAME OR PASSWORD SUPPLIED AND YET IT IS ... >>Exchange will only deny relay after accepting the ... > that Exchange is authenticating the session without any ... > You wont be rejected and the test did authenticate without ...
    (microsoft.public.exchange2000.setup.installation)