Delay 4.4.7 NDR

We recently started getting NDR Could not deliver the message in the time limit specified 4.4.7 messages from certain domains ( and

What has changed was we moved our Exchange 2003 Server to a new location, changed the IP/subnet address of our Exchange Server, changed IP address/subnet of WINS/DNS and our firewall remains same.

Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Out of curiosity, did you update your PTR record associated with the external IP address of your Exchange server(s).  Some anti-spam software is throttling e-mail messages from domains without a PTR to 1 message an hour or 10 messages an hour, etc.  This 4.4.7 sometimes appears in this case.
ajruizAuthor Commented:
Our PTR address remains the same and there was no need to update it.
So the address of the Exchange server changed, but the NAT did not change, correct?
Your Guide to Achieving IT Business Success

The IT Service Excellence Tool Kit has best practices to keep your clients happy and business booming. Inside, you’ll find everything you need to increase client satisfaction and retention, become more competitive, and increase your overall success.

ajruizAuthor Commented:
So your exchange server is now talking to a different DNS server?
ajruizAuthor Commented:
It is the same DNS server just with a different IP Address.
So just to moved the DNS server and the Exchange server to different subnets?
ajruizAuthor Commented:
Yes.  We have two DNS servers, one at the new location and one at the old location.
This seems like a DNS problem to me.  Was the Exchange server pointed to both DNS servers before or still just the one?  Can you ping and from your Exchange server's subnet?
ajruizAuthor Commented:
We block ping from the firewall.  I just noticed both mail ip addresses we are having issues with start with 192.  We did a tracert and it isn't getting to the default gateway.  It appears to be switch related but we can't figure it out.
Does your internal network start with 192. as well?  If so you may run into some routing problems.  You may need to setup some static routes in order to get the traffic out to these mail addresses.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
ajruizAuthor Commented:
Ours do not start with 192.  We are having Cisco look into it also.  
Ok, yeah...this is looking less and less like a Windows problem...leaving my realm.  hehe
ajruizAuthor Commented:
Okay, I figured it out.  We are on a cluster, initially we configured per a KB article where the private heartbeat was set to which worked fine at our old location.  When we moved it to our new location we are using the 10 as the first octet so when it was first brought up e-mail would not go through.  We changed it to figuring 192 was reserved.  You guessed it, e-mail was trying to go out the private heartbeat for e-mails going to the 192 range.
Aha!  Interesting...well I'm glad you got it figured out.  Clustering can be problematic at times.
I'm having the same problem but I'm not on a cluster.

We recently changed from one ISP to another with different DNS and IPs.

What check list can I do to go and find out what is wrong with our system?
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.