Internal mailflow not working between exchange 2007 and 2010 servers.

Internal mailflow not working between exchange 2007 and 2010 servers.what needs to be check its an new migration or transition.
Yogesh_Exchange_ExpertAsked:
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.

Yogesh_Exchange_ExpertAuthor Commented:
below error is coming when i am doing message tracking..

The last attempt to send the message was at 10/18/2011 1:19:07 PM (UTC-07:00) Mountain Time (US & Canada) and generated the error '451 4.4.0 Primary target IP address responded with: "421 4.3.2 Service not available, closing transmission channel." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts.'.
0
AkhaterCommented:
service not available is usually a routing issue

are they both in the same AD site? can you telnet from one server to the other on port 25? do you have any kind of firewall between them ?

1. Make sure you can telnet from one to the other and that you are getting the Exchange banner as reply
2. Make sure that SMTP inspection is DISABLED on the firewalls
3. make sure DNS resolution is working between the two
0

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
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
Exchange

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.