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

x
?
Solved

Outlook Flooded with Undeliverable Emails

Posted on 2015-02-10
4
Medium Priority
?
20 Views
Last Modified: 2016-06-03
Have a real strange problem here folks...

Environment is SBS 2010 with WIN7 clients, running Office 2010. There are 8 people in this environment and they all seem fine but one person who keeps getting undeliverable bounce backs on his outlook client, they all seem to come from the same domain, always with a barracuda error message. Here's the trick however, I have tested and re-tested their domain against blacklists and they are clean as a whistle, send an Email to myself on both my hotmail account and my exchange account (hosted on the cloud by intermedia) and they came through just fine. So it almost looks like outlook is just generating these bounce backs without even trying to send the Emails? Very strange...
0
Comment
Question by:Marvio_Santos
[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
  • 2
4 Comments
 
LVL 31

Expert Comment

by:Gareth Gudger
ID: 40601556
I assume this means the user actually send to this domain originally and is getting rejected? If so, can you post the NDR here?

If they never sent to this domain this is likely just a backscatter attack. More info on a backscatter attack here. If it is, not much you can do except get a really good message-hygiene solution that can protect against this, or, blacklist that domain.
http://en.wikipedia.org/wiki/Backscatter_(email)
0
 
LVL 1

Accepted Solution

by:
Marvio_Santos earned 0 total points
ID: 40601646
I finally figured it out... They did have a virus infection a while back, but exchange was still trying to send the Emails from back when, cleared out all the queues and it was fine
0
 
LVL 31

Expert Comment

by:Gareth Gudger
ID: 40601732
Glad you got it going. That must have sent out thousands of emails to still be processing, even now. Did you get blacklisted?
0

Featured Post

On Demand Webinar: Networking for the Cloud Era

Did you know SD-WANs can improve network connectivity? Check out this webinar to learn how an SD-WAN simplified, one-click tool can help you migrate and manage data in the cloud.

Question has a verified solution.

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

If you’re involved with your company’s wide area network (WAN), you’ve probably heard about SD-WANs. They’re the “boy wonder” of networking, ostensibly allowing companies to replace expensive MPLS lines with low-cost Internet access. But, are they …
By default Outlook 2016 displays only one time zone in the Calendar. The following article explains how to display two time zones in one calendar view.
Internet Business Fax to Email Made Easy - With  eFax Corporate (http://www.enterprise.efax.com), you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, f…
Monitoring a network: why having a policy is the best policy? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the enormous benefits of having a policy-based approach when monitoring medium and large networks. Software utilized in this v…
Suggested Courses

670 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