Keep getting this NDR from a few domains

[kooma]

Very Strange.. I keep getting this :

Your message did not reach some or all of the intended recipients.

Subject: Testing
Sent: 11/14/2003 2:23 AM

The following recipient(s) could not be reached:

xxx@domain.com on 11/14/2003 2:23 AM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<exchangeservername.domain.com #5.5.0 smtp;550-Verification failed for <username@domain.com>


Anyone know what this is?? All users can send pretty much 100% only a few get this to a couple of different domains (about 10 or so).

Can't find anything anywhere on this NDR....

HELP!

 

[Marcs41]

Well, since you know where the NDR is coming from, contact them to see if you are not on some BlackList by any chance.
Email them from another domain, or Hotmail or so.

Marc
[sub]If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
Free Tip: The F1 Key does NOT destroy your PC![/sub]

 

[kooma]

This is a brand new exchange server only up two days! I did check and no not blacklisted.

Any other ideas?

 

[Marcs41]

Not without more info.
You never told us which server gives you the 550, yours or theirs?

Marc
[sub]If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
Free Tip: The F1 Key does NOT destroy your PC![/sub]

 

[mcnuttlaw]

Be sure Smart Hosting is not set.

 

[Marcs41]

That is bad info mcnutlaw.
SmartHost is easy and for some the only way to send to any domain without problems.
It also keeps your queues to a minimum.
If you want full control, don't use it, otherwise, it is just fine, and in most cases recommended.

Marc
[sub]If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
Free Tip: The F1 Key does NOT destroy your PC![/sub]

 

[kooma]

Sorry. I get this NDR from my own server, I think! I try to send to the email addresses (there are more than one) and I get this NDR back in my inbox. I have to assume it is coming from my server. But honestly I do not know.

 

[Marcs41]

What do you mean you do not know?
The System Admin or whathever sending you the NDR has an address, read it.
The message also states WHICH address could not be reached.
Are you the Exchange Admin?

 

[kooma]

It was the PTR record for the IP that my mail server uses. My ISP did not create it.

With all the SPAM these days, best to always check your reverse DNS first. A two second check could save you hrs of work ....