Outboud messages sit in Queue with the following error 451 4.4.0 primary target IP address responded with "421.4.4.2 unable to connect."

I have just installed Exch2007 and am having problems with sending mail.

Messages just sit in the queue with the follwoing error message:

451 4.4.0 primary target IP address responded with "421.4.4.2 unable to connect."attempted failover to alternate host, but that did not succeed.Either there are no alternate hosts, or delivery failed to all alternate hosts.

Any ideas what is wrong or what I shoudl be checking?

Incoming mail is fine.

Exchange 2007 SP1
Server 2008 x64
LVL 2
grahamsmythAsked:
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.

marques_salazarCommented:
Are you getting event id 2019?
0
grahamsmythAuthor Commented:
I don't see that event coming through.

I have attached a copy of the event log.
System-Events.txt
0
grahamsmythAuthor Commented:
Managed to figure it our - Transport Service would not start due to IPv6 being disabled!!!
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
Email Protocols

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.