Solved

Can't send mail to a server with a bad MX record

Posted on 2006-06-30
3
286 Views
Last Modified: 2010-03-06
CompanyA running Exchange Server 2000 and attempting to send mail but getting delivery failures to CompanyB which has two MX records:

mail1.companyb.com, preference 5
mail2.companyb.com, preference 10

If I telnet to port 25 of mail1.companyb.com, it responds with:
550 Requested action not taken: mailbox unavailable
Then it drops the connection.

CompanyA's Exchange server never attempts to go to mail2.companyb.com to deliver mail.  Instead, it just issues all users at CompanyA a delay, and then eventually a failure.  

I have other clients running Exchange 2003 server, and they can deliver mail to CompanyB.  Is there a setting on the Exchange 2000 server?
0
Comment
Question by:jasonkthomas
[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 Comments
 
LVL 104

Accepted Solution

by:
Sembee earned 125 total points
ID: 17019453
The remote server isn't sending back a failure message that the Exchange server recognises, or something is stopping it from being received correctly.
Exchange doesn't know that the message has a fatal failure, and therefore continues to try the primary MX record.
There is no setting to change in Exchange, because Exchange is doing what it is designed to do.

What do you have between the server and the internet? A firewall of some kind? Does it have SMTP scanning capabilities?
Anything else that could be interfering with SMTP traffic? Antivirus, Antispam etc?

Simon.
0

Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

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

Suggested Solutions

Find out what you should include to make the best professional email signature for your organization.
How to resolve IMCEAEX NDRs in Exchange or Exchange Online related to invalid X500 addresses.
In this video we show how to create a Resource Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: Navigate to the Recipients >> Resources tab.: "Recipients" is our default selection …
This video shows how to quickly and easily add an email signature for all users on Exchange 2016. The resulting signature is applied on a server level by Exchange Online. The email signature template has been downloaded from: www.mail-signatures…

752 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