Unable to receive external mail - Exchange 2010


I have just installed a fresh copy of exchange 2010 and unable to receive external mail.

It is receiving internal mail and sending internal/external mail.

I can ping the mail server and telnet onto port 25.

I have created a new receive connector with the following settings: FQDN (mail.mydomainname.co.uk) - Local IP address (All available IPv4) (Port 25) - Remote server (mail server IP address) - Authentication (TLS) - Permissions (Anonymous, Exchage Users, Exchange Servers, Legacy Exchange).

When sending the email the sender receives the following bounce back

Your message wasn't delivered because of security policies. Microsoft Exchange will not try to redeliver this message for you. Please provide the following diagnostic text to your system administrator.

The following organization rejected your message:

Anything I should be checking ?

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.

Have you checked the SPAM filter to see if it is blocking somehow?
PlancomAuthor Commented:
"Have you checked the SPAM filter to see if it is blocking somehow?"

is that in the exchange management console ?
Is your MX record pointing to the exchange server and you have an address routed to the mail server in you firewall/router?
Determine the Perfect Price for Your IT Services

Do you wonder if your IT business is truly profitable or if you should raise your prices? Learn how to calculate your overhead burden with our free interactive tool and use it to determine the right price for your IT services. Download your free eBook now!

Have you restart the hub server after creating new receive connector
I believe that your MX records for your email domain is working just fine. You existing Receive Connector e.g. Default Connector. test to check on "Anonymous" on permission and then restart the Hub server.

Is your anti-spam will facing to internet and your MX records will point to anti-spam? if yes, also check on anti-spam sttings. Like mine, I have to set configure so that email received by anti-spam able to pass to Hub Transport server.
PlancomAuthor Commented:
I have restarted the exchange and domain controller after setting up the connector.

All the connectors (default, client and custom) have anonymous ticked.

i dont have any 3rd party anti spam installed at the moment.
PlancomAuthor Commented:
Anyone know what else I could try?

Are you by chance sending to a distribution group or something?  Does email to a standard user work ok?  I have seen this in the delivery options where there is a checkbox that states must be autheticated to send mail to this group etc under a distribution group.  

Like this:

    1) Open the Exchange Management Console
    2) Expand Recipient Configuration
    3) Click Distribution Group
    4) Double click the distribution group
    5) Select the Mail Flow Settings Tab
    6) Double click Message Delivery Restrictions
    7) Uncheck “Require that all senders are authenticated“
    8) Click OK

This will allow senders (externally) to email to the specific group, where if this box is checked you would only use it internally for like company newsletters etc.
Since you are receiving email from External. Could we try troubleshoot from this. Use your external account (GMAIL) send a test mail to the yourself ( your company mailbox). If the message not reach your Exchange server then your GMAIL will receive a bouncing message. Then please post the error message or any related to it. May I know your email domain so that I can verify if my email gateways able to resolve it.
Disable the old receive connector temporarily, create a new one and see if mail flows. What are the permissions on the receive connector? I assume inbound email has worked before? Have you checked the firewall setting to verify you are allowing port 25 inbound?
PlancomAuthor Commented:

I send an email to the mailbox from an external email address (talk21 account) and got the following bounce back

Sorry, we were unable to deliver your message to the following address.

Remote host said: 550 5.7.1 Unable to relay for rriaz@debt-specialists.co.uk [RCPT_TO]

--- Below this line is a copy of the message.

Received: from [] by nm24.bullet.mail.ukl.yahoo.com with NNFMP; 04 Apr 2012 15:27:09 -0000
Received: from [] by tm10.bullet.mail.ukl.yahoo.com with NNFMP; 04 Apr 2012 15:27:09 -0000
Received: from [] by omp1003.bt.mail.ukl.yahoo.com with NNFMP; 04 Apr 2012 15:27:09 -0000
X-Yahoo-Newman-Property: ymail-3
X-Yahoo-Newman-Id: 1317.5986.bm@omp1003.bt.mail.ukl.yahoo.com
Received: (qmail 30742 invoked by uid 60001); 4 Apr 2012 15:27:08 -0000
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1333553228; bh=SddowPiJ2fs+AVINKoWwAPQsTHepTSj3mkCcuCQ1ARo=; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=bM/ZoPRjx2WBu4fslSepdSfVbEIgxeRE6aKgEwfrUBq8Pn78ZMSFlLnFqW56WYlbH2YqFJHivWTinjrfPQpsI1QzCWHs0htm57pKsCznVVHosyk0c3rnDweBjSsrvUUJk6JMqtC0nGwT2ZKh89mZoKCJh2iTqrMBMPwoS+Aj93I=
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
  s=s1024; d=talk21.com;
So if you were to possibly ping or do an NSlookup of mail.domainname.com etc, that would resolve to the external IP address of the business/server?  You would have to do the NSlookup outside the network or specify a name server outside the network.  

Q1)  Who currently does your mail now, was this a pop account thing prior to exchange?

I would contact whoever is hosting your MX record and verify mail is now pointing to the correct address of the business.  You can send/recieve internal, and send external mail.  It just sounds like it would be something with the pointers in the outside world in routing the mail, or port 25 inbound is closed.  

The error above vaguely states your mailserver does not exist and cannot be found.  So a record/pointer needs to be created/pointed to your server.

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

From novice to tech pro — start learning today.