Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

sbs 2003 Exchange 2003, How to tell where mail is getting in the queue from

Posted on 2012-04-09
9
Medium Priority
?
398 Views
Last Modified: 2012-06-18
My exchange server queues keep filling up with a bunch of junk spam mail.  It is addressed like it is coming from the postmaster on our server but it isnt.  I have verified that i am not a open relay.  I tried 3 different open relay tests and they all pass.  We get our emails only through postini and i only allow their server ip addresses to forward into our server through the firewall.  But i cant figure out where it is coming from.  I just deleted over 180000 spam messages from the queue.  The worst part is it keeps getting us blacklisted.  Most companies are pretty nice and remove us quickly from the list but i'm sure they arent going to keep being that nice if i cant figure it out.
0
Comment
Question by:charles18602
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
  • 2
  • +2
9 Comments
 
LVL 3

Expert Comment

by:tobyweston
ID: 37825315
Is it possible to get an example of the headers in one of these emails?
0
 
LVL 9

Expert Comment

by:Geodash
ID: 37825317
Verify your MX record and SPF record at http://www.kitterman.com/spf/validate.html

SPF record, if you don't have one in place, should help alleviate this.
0
 
LVL 9

Expert Comment

by:Geodash
ID: 37825330
In case you do not know what an SPF record is - read here -

http://en.wikipedia.org/wiki/Sender_Policy_Framework
0
Get free NFR key for Veeam Availability Suite 9.5

Veeam is happy to provide a free NFR license (1 year, 2 sockets) to all certified IT Pros. The license allows for the non-production use of Veeam Availability Suite v9.5 in your home lab, without any feature limitations. It works for both VMware and Hyper-V environments

 
LVL 9

Expert Comment

by:Geodash
ID: 37825341
Also, do you use any kind of inbound/outbound SPAM filter?
0
 
LVL 22

Expert Comment

by:chakko
ID: 37825344
that could be a NDR type of attack.

In the Exchange IMF you can select a checkbox to disable NDR for a little while and see if that stops it.

this page shows where to turn it off

http://www.emailquestions.com/microsoft-exchange/311-disable-ndrs-exchange-2000-2003-a.html
0
 
LVL 22

Expert Comment

by:Larry Struckmeyer MVP
ID: 37825511
Agreed that the most likely is NDR.  It is also possible that some bot has addressed mail directly to the IP address of your server, not the mx record, in which case it would bypass your off site filters.  The headers should tell you.
0
 
LVL 76

Accepted Solution

by:
Alan Hardisty earned 2000 total points
ID: 37825551
Disabling NDR's is against RFC standards so please do NOT turn them off.

Your problem by the sounds of it is NDR spam which means Postini are not rejecting mail destined for Invalid Recipients.

You should find that you are listed on www.backscatterer.org and you can determine this on www.mxtoolbox.com/blacklists.aspx

You either need to get Postini to filter invalid recipients for you or stop using Postini and use another provider who can filter invalid recipients.

As soon as Postini accepts an email destined for an Invalid account and passes it on to you, your server becomes responsible for sending back an NDR.  If they reject emails destined for invalid Recipients, then the sending server is responsible for the NDR and thus your problem will go away.

Alan
0
 
LVL 22

Expert Comment

by:chakko
ID: 37825599
I would just turn off the NDR to control the problem for now.  You can turn it on later to deal with the problem more permanently.
0
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 37825620
I would suggest tackling the source of the problem, rather than digging yourself a bigger hole by turning off NDR's.
0

Featured Post

What Is Blockchain Technology?

Blockchain is a technology that underpins the success of Bitcoin and other digital currencies, but it has uses far beyond finance. Learn how blockchain works and why it is proving disruptive to other areas of IT.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article lists the top 5 free OST to PST Converter Tools. These tools save a lot of time for users when they want to convert OST to PST after their exchange server is no longer available or some other critical issue with exchange server or impor…
There are times when we need to generate a report on the inbox rules, where users have set up forwarding externally in their mailbox. In this article, I will be sharing a script I wrote to generate the report in CSV format.
how to add IIS SMTP to handle application/Scanner relays into office 365.
There are cases when e.g. an IT administrator wants to have full access and view into selected mailboxes on Exchange server, directly from his own email account in Outlook or Outlook Web Access. This proves useful when for example administrator want…
Suggested Courses

715 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question