Error message...every now and then

[sxwk12]

I am having this problem on different email addresses outside of our company. One minute I get this meesage to a certain recipient, next minute I resend and it goes through. Is this a problem on my end? According to the message, it is on their end. But why would the messages not go through one minute but go through the next minute? This message is also a little misleading because my boss hit reply to one of her emails and got this message, so the server is in the dns.



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.
<abc.123.COM #5.4.0>


Exchange 2000
Win 2000

Sidney
sidney@tsisc.com

[gunderstone]

Intermittant DNS issues will cause these types of issues. Its the same when one minute you can reach yahoo.com and another minute you can't and then you suddenly can again.

This is beyond your control in most cases.

The only way this is an internal issue is if your internal DNS server is not performing forward lookups correctly intermittantly.

If the DNS server your clients uses to resolve the company.com MX record suddenly do not perform a forward lookup properly you will have this happen.

Are the emails that fail all from one company or if the issue happens right now do multiple companies suddenly become unavailable to get email off to?

[jsipe]

Do you have more than one Exchange server? Have you configured your Exchange server with any special instructions for DNS resolution, or is it at the default settings? Is more than one DNS server specified on the Exchange server's TCP/IP properties?

This problem is intermittant, is it happening more often than not?

Since the reporting server is "abc.123.COM #5.4.0" (assuming that's your server, and is masked for privacy) , the problem is either on your end, or on their end but in the way their DNS configuration is set up (i.e. if their MX record is missing, or their DNS servers are down).

I gather from the initial post that you are having this problem sending to more than one domain, so it is most likely on your end.

Try to be as specific as possible when replying and I'll see if I can help.

James

-Just noticed Gunder beat me to this one. ;) I'll still see if I can help with a little more info.

[gunderstone]

Please, if you have anything to add jump right in, two ideas are better than one.

:D

[sxwk12]

It's actually only happening to one domain that we are trying to send to. I figured it was on their end but we have been having several email problems (open relay, which we have now closed) in the past few weeks and other little problems that I did not want to go and blame someone else unless I was sure.

Thanks for the help.
Sidney

[jsipe]

Sidney,

one good way to tell if it's you or not is to eliminate your DNS server from the equation. A tool that can be usefull for this can be found here http://centralops.net/co/ . I have no affiliation with that site, but the online nslookup is easier to use than the command based one when switching servers.

If you can see their MX record, and that record points to an A record, which you can also see, then that is all you need for email delivery to work properly as far as name resolution goes. (you can have strange delivery problems if the MX points to an IP, which some DNS servers allow you to do)

Since this is intermittant, if you can try a lookup from a DNS server other than your own during the problem, and you can see both records, then try it on your DNS server during that same timeframe, and compare records, this should tell you to some degree if the problem is with your server or not. This is of course assuming that the problem is consistant for a given peroid of time.

Also, your DNS server should probably be caching the information. So, if it finds it once, the data should be there for the next time it tries to get it.

If you're not comfortable with the process, if you give me the domain you're tring to send to, I'll look to see if the DNS for the domain looks ok.