Solved

Exchange 2010 refused connection from sender

Posted on 2013-12-25
6
659 Views
Last Modified: 2014-01-02
Dear Expert,

I have a customer that cant send email to us recently, the log they provided state below,

2013-12-24 17:29:22,OUTBOUND,jmchen@efgh.com.tw<mailto:jmchen@efgh.com.tw>(172.21.36.135),joyce@abc,com<mailto:joyce@abc,com>(101.99.x.x-mail.abc,com<http://101.99.x.x-mail.abc,com>),967613063,22545,QUEUED,601,Deferred: Connection refused by mail.abc,com<http://mail.abc,com>
2013-12-24 17:29:22,OUTBOUND,miahsieh@efgh.com.tw<mailto:miahsieh@efgh.com.tw>(172.21.36.135),joyce@abc,com<mailto:joyce@abc,com>(101.99.x.x-mail.abc,com<http://101.99.x.x-mail.abc,com>),513374723,53521,QUEUED,601,Deferred: Connection refused by mail.abc,com<http://mail.abc,com>
2013-12-24 17:29:22,OUTBOUND,jmchen@efgh.com.tw<mailto:jmchen@efgh.com.tw>(172.21.36.135),joyce@abc,com<mailto:joyce@abc,com>(101.99.x.x-mail.abc,com<http://101.99.x.x-mail.abc,com>),914463265,13973,QUEUED,601,Deferred: Connection refused by mail.abc,com<http://mail.abc,com>
2013-12-24 17:29:22,OUTBOUND,miahsieh@efgh.com.tw<mailto:miahsieh@efgh.com.tw>(172.21.36.135),joyce@abc,com<mailto:joyce@abc,com>(101.99.x.x-mail.abc,com<http://101.99.x.x-mail.abc,com>),1285071653,25209,QUEUED,601,Deferred: Connection refused by mail.abc,com<http://mail.abc.com>


I did check their domain name, the spf and reversed dns is not found.

could it be the cause?

remarks: only this customer is having problem to send email to us

Thanks
Alfred
0
Comment
Question by:patcheah
6 Comments
 
LVL 7

Expert Comment

by:dsnegi_25dec
ID: 39739741
Yes ...........
0
 
LVL 8

Assisted Solution

by:vSolutionsIT
vSolutionsIT earned 25 total points
ID: 39739767
Ask them to check if their email server's ip address is blacklisted or not. If yes then they will have to get it removed from the blacklists.
Do you have your email server's configured to check reverse DNS ? if yes then it could be the issue.
0
 
LVL 36

Expert Comment

by:Mahesh
ID: 39739876
Yes, VSolutionIT is right..

Your Email server must be configured to check \ verify Sender's SPF record and if they don't have or got blacklisted, emails sent by them will be rejected by your server

Mahesh
0
Does Powershell have you tied up in knots?

Managing Active Directory does not always have to be complicated.  If you are spending more time trying instead of doing, then it's time to look at something else. For nearly 20 years, AD admins around the world have used one tool for day-to-day AD management: Hyena. Discover why

 
LVL 4

Expert Comment

by:Pradeep VIshwakarma
ID: 39739925
You must request a REVERSE DNS ENTRY from your ISP who issued the block of IP ADDRESSES.

The NAME and IP ADDRESS to which is mapped MUST EXACTLY MATCH THE HOSTNAME OF THE MAIL SERVER SENDING THE E-MAIL.

If you use one IP ADDRESS to send for multiple domains, make certain the mapping matches the domain name of your HOSTING COMPANY and the setup a PTR RECORD for each hosted domain in the DNS for the hosted domain.

You should also set up REVERSE DNS on your local DNS SERVERS and create a PTR record for each of the hosted domain's HOST records which maps to the MX record for the e-mail.
0
 
LVL 25

Accepted Solution

by:
Marcus Bointon earned 25 total points
ID: 39740188
Notice that those errors in the logs are deferrals due to connection being refused, not bounces. "Connection refused" is not an SMTP-level issue - it's lower-level than that; I would check that they (or possibly their upstream ISP) are not blocking outbound SMTP. Blacklisting and reverse IP blocking typically happens within the SMTP layer, and should result in 5.1.7 status bounces, or at least 4.1.7 deferrals, neither of which are happening here.

A missing SPF is not a valid reason for rejection; the only basis for SPF rejection is a definitive 'FAIL' status, and many receivers (stupidly, since it defeats the entire point of it) do not even do that, and again, it's an SMTP-layer check and should result in a bounce. Insisting on matching reverse DNS is a reasonable anti-spam technique, but will often reject a mail from legitimate sources, such as gmail which often has mismatching reverse IPs (because they have such a high turnover of servers).
0
 

Author Closing Comment

by:patcheah
ID: 39750958
Thanks experts.

Request sender to add spf record. So far so good now. Happy New Year!
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

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

Marketers need statistics and metrics like everybody else needs oxygen. In this article we explain how to enable marketing campaign statistics for Microsoft Exchange mail.
This article aims to explain the working of CircularLogArchiver. This tool was designed to solve the buildup of log file in cases where systems do not support circular logging or where circular logging is not enabled
In this video we show how to create a Distribution Group 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 >>…
In this Micro Video tutorial you will learn the basics about Database Availability Groups and How to configure one using a live Exchange Server Environment. The video tutorial explains the basics of the Exchange server Database Availability grou…

770 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