Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium


email can't be delivered to valid recipient address

Posted on 2004-11-22
Medium Priority
Last Modified: 2012-06-21
Hello. I have a problem with email to a business partner that we have been sending stuff to for years but suddenly all our email is bounced back as non-deliverable. I have been talking with them and they say nothing has changed of their end. Nothing has changed on our end for certain. It's only email from us to them that gets rejected (tested with yahoo email and it works fine) and we are able to recieve from them. Has anyone run into a similar situation before?

We have microsoft exchange 2000 (latest SP and patches). The smtp message queue properties say that a smtp protocol error has occuredd but donesn't specify any additional info. Below are copies of the error messages I have received while testing:

 The destination server for this recipient could not be found in Domain Name Service (DNS).  Please verify the email address and retry.  If that fails, contact your administrator.
            <ubgexchange.unitybuilders.com #5.4.0>

Could not deliver the message in the time limit specified.  Please retry or contact your administrator.
            <ubgexchange.unitybuilders.com #4.4.7>

The e-mail system was unable to deliver the message, but did not report a specific reason.  Check the address and try again.  If it still fails, contact your system administrator.
            <ubgexchange.unitybuilders.com #4.0.0 smtp;417 DNS lookup failure: unitybuilders.com.  Try again later.

Any ideas?
Question by:SirTravis
LVL 24

Accepted Solution

David Wilhoit earned 750 total points
ID: 12648346
Looks like they've played with their DNS servers recently, I actually did a lookup and their records showed internal IP addresses. What a mess!


Clear the DNS cache on your DNS servers, or, delete the cached entry for that domain. REstart the DNS server service, and client service. On the exchange server, run ipconfig /flushdns, and then retry the messages.


Author Comment

ID: 12660866
I shall try it


Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering 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

Exchange administrators are always vigilant about Exchange crashes and disasters that are possible any time. It is quite essential to identify the symptoms of a possible Exchange issue and be prepared with a proper recovery plan. There are multiple…
In this post, we will learn to set up the Group Naming policy and will see how it is going to impact the Display Name and the Email addresses of the Group.
A short tutorial showing how to set up an email signature in Outlook on the Web (previously known as OWA). For free email signatures designs, visit https://www.mail-signatures.com/articles/signature-templates/?sts=6651 If you want to manage em…
Whether it be Exchange Server Crash Issues, Dirty Shutdown Errors or Failed to mount error, Stellar Phoenix Mailbox Exchange Recovery has always got your back. With the help of its easy to understand user interface and 3 simple steps recovery proced…
Suggested Courses
Course of the Month11 days, 16 hours left to enroll

564 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