?
Solved

Exchange 2010 Backscatter problem

Posted on 2011-03-15
5
Medium Priority
?
2,822 Views
Last Modified: 2013-03-28
We are having an issue in Exchange 2010 that i believe is being caused by Backscatter. Recently I have noticed a bunch of messages in the Exchange Queue Viewer that keep trying to resend but are unable to connect. All of these messages are Non Delivery Reports for undeliverable spam email that was sent to our server.

Yesterday afternoon i tried enabling Recipient Validation in exchange. Since turning this feature on we have gone from over 60 messages trying to resend over and over to only 8 after enabling. This seems to have helped the situation, however i am still seeing messages trying to resend.

I found a few articles related to this issue that also recommended completely disabling NDR's all together, or adding another layer of spam detection. Is there any other recommended course of action to resolve this problem? Aside from valid NDR's not being sent, is there any other down side to disabling NDR's? Is there a rule in Exchange we can setup to drop off the NDR's that fail to connect after the first or second try?

Here is alittle background on our current anti-spam setup. Our first layer of anti-spam detection is our Sonicwall firewall which has RBL entries for spamhaus,  dnsbl.sorbs, barracudacentral, & spamcop. For the second layer we are using Trend Micro Scan Mail for Exchange. This product doesn't seem to do a good job of cleaning any spam getting through the firewall. I am looking at alternatives as our subscription is up in a few months. Any recommendations on anti-spam products you are having success with are greatly appreciated.

For reference here is a sample of one of the messages currently trying to resend.

Identity: qualissrv01\57782\232009
Subject: Undeliverable: Loan offer at 3% Interest Rates!!
Internet Message ID: <b925383a-19d1-415d-a701-f6acd8184eae@Qualisauto.com>
From Address: <>
Status: Ready
Size (KB): 6
Message Source Name: DSN
Source IP: 255.255.255.255
SCL: -1
Date Received: 3/14/2011 8:20:10 PM
Expiration Time: 3/16/2011 8:20:10 PM
Last Error: 450 4.1.1 <ocean@lbasantarem.com.br>: Recipient address rejected: User unknown in local recipient table
Queue ID: qualissrv01\57782
Recipients:  ocean@lbasantarem.com.br

Thank you
0
Comment
Question by:qualis_auto
[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
5 Comments
 
LVL 76

Accepted Solution

by:
Alan Hardisty earned 2000 total points
ID: 35139363
Okay - do you receive mail directly to your server or does a 3rd party filter your mail and pass it on to you?

If via a 3rd party - THEY have to Recipient Filter.

If you receive it directly, you need to install the Anti-Spam options and enable Recipient Filtering.

http://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/A_4257-Exchange-2007-2010-Backscatter-and-how-to-resolve-it.html
0
 

Author Comment

by:qualis_auto
ID: 35141111
We receive our mail directly. I turned on the Anti-Spam options and enabled the Recipient Filtering and that seems to have done the trick. Thanks for the help Alanhardisty.
0
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 35141401
You are welcome.  Glad all is happy now.  Make sure you get delisted fron Backscatterer.org (usually happens automatically after about 4 weeks).

Thanks for the points.

Alan
0
 

Expert Comment

by:jambear
ID: 39028606
Thanks for this info. The same thing is happening at my office. I enabled the filtering and I'm still having this issue. is there something else that I can try? Any help would be appreciated. Not sure what else to try here. thanks in advance.
0
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 39029216
jambear - your best bet is to open up your own question (if you have not already) and then ping me a link and I'll see what I can do to help you.  Or drop me an email.

Alan
0

Featured Post

What does it mean to be "Always On"?

Is your cloud always on? With an Always On cloud you won't have to worry about downtime for maintenance or software application code updates, ensuring that your bottom line isn't affected.

Question has a verified solution.

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

Encryption for Business Encryption (https://en.wikipedia.org/wiki/Encryption) ensures the safety of our data when sending emails. In most cases, to read an encrypted email you must enter a secret key that will enable you to decrypt the email. T…
After hours on line I found a solution which pointed to the inherited Active Directory permissions . You have to give/allow permissions to the "Exchange trusted subsystem" for the user in the Active Directory...
In this video we show how to create a Shared Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >> Sha…
This video demonstrates how to sync Microsoft Exchange Public Folders with smartphones using CodeTwo Exchange Sync and Exchange ActiveSync. To learn more about CodeTwo Exchange Sync and download the free trial, go to: http://www.codetwo.com/excha…
Suggested Courses

771 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