Hello,

I am having an issue sending out external emails. Here is some background information to give anyone who looks at this a better understanding of my setup.

1. This is a lab setup/test environment for educational purposes only.

2. Exchange 2013 - CAS and Mailbox Roles

3. Windows Server 2012 R2 (Exchange server, IIS 8) 192.168.21.7

Windows Server 2012 R2 (Hyper-V Host) 192.168.21.5

Windows Server 2012 R2 (P-AD.DC, DNS, DHCP, File Share) 192.168.21.6

4. All DNS Records are set to 192.168.21.6, 8.8.8.8

I have having an issue sending out external emails. I do not have a registered domain. I can send emails internally just fine. Externally I get this message:

Diagnostic information for administrators:

Generating server: LAB-EXCH01.LAB.local

jeff@xxxx.net
LAB-EXCH01.LAB.local #550 5.7.1 Unable to relay
##

Original message headers:

Received: from LAB-EXCH01.LAB.local (192.168.21.7) by LAB-EXCH01.LAB.local
 (192.168.21.7) with Microsoft SMTP Server (TLS) id 15.0.516.32; Wed, 1 Jul
 2015 08:12:07 -0500
Received: from LAB-EXCH01.LAB.local ([fe80::c548:af7a:daed:xxxx]) by
 LAB-EXCH01.LAB.local ([fe80::c548:af7a:daed:xxxxx]) with mapi id
 15.00.0516.029; Wed, 1 Jul 2015 08:12:07 -0500
From: Jeffrey  <JEFF@lab.local>
To: "jeff@xxxx.net" <jeff@xxxxx.net>
Subject: test
Thread-Topic: test
Thread-Index: AQHQs/+FRlO3GUcXlkSB0RliYPjFxg==
Date: Wed, 1 Jul 2015 13:12:07 +0000
Message-ID: <aab65014724f47bbb634fd0998fad498@LAB-EXCH01.LAB.local>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [50.192.xx.xx]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
------------------------
I have a Frontend Receive Connector Relay setup, with Anonymous users checked. I was told I could send out emails with a local domain but could not receive them.
After setting up the relay, I would get a different error on occasions stating I did not have Authentication. Then my local emails wouldn't work.
Any help would be much appreciated.

What is your intent?  Are you relaying email from your lab servers through some production servers to the Internet?  the relaying denied error sounds like you are missing a setting on your receive connector.  If you go to your FrontEnd receive connector, what do you have selected under 'Authentication'
(under security on the connector).  Do you have 'Externally Secured' checked?  If you do not, then this is why your server won't relay the email to an external address.  In order to select this, you must make
sure that you have 'Exchange Servers' selected under 'Permissions'. 

** You may have to clear other setting depending on how you have the connector configured.

While I don't recommend this with an internal domain that should not be relayed, I believe
this will work for what you are attempting to accomplish.

See this article for more information: https://technet.microsoft.com/en-us/library/jj657472(v=exchg.150).aspx

Hello Damian,

Thanks for the response. For your question what is my intent: I am doing this to better myself and become more knowledgeable of how to setup and manage an Exchange Server. I work for an IT Tech company and a desktop support technician. I have created a test/lab environment with some old servers my company has here as test environments and educational purposes.

I am testing by sending an external email to my email here at my company only.

As far as your answer, you are correct. I was missing some settings checked. I followed this guide http://www.petenetlive.com/KB/Article/0000891.htm

Which is what you explained.

My issues now is the emails are not being sent out. They are stuck in the Queue Tool Box:

Identity: LAB-EXCH01\13\163208757292
Subject: test
Internet Message ID: <44ece4e949f74bf092eaaa667a8f1ba3@LAB-EXCH01.LAB.local>
From Address: JEFF@lab.local
Status: Retry
Size (KB): 3
Message Source Name: SMTP:Default LAB-EXCH01
Source IP: 192.168.21.7
SCL: -1
Date Received: 7/1/2015 9:55:57 AM
Expiration Time: 7/3/2015 9:55:57 AM
Last Error: 451 4.7.0 Temporary server error. Please try again later. PRX2
Queue ID: LAB-EXCH01\13
Recipients: email at test.com 4.7.0 Temporary server error. Please try again later. PRX2 ;0;CN=Internal Send Connector,CN=Connections,CN=Exchange Routing Group (DWBGZMFD01QNBJR),CN=Routing Groups,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=LAB,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=LAB,DC=local

I just looked over the error message you posted, and to be honest, I have not seen a message queue up like this. Take a look at these links for help [all rotate around DNS configuration on Exchange]

http://blog.kloud.com.au/2013/11/22/exchange-2013-dns-settings-cause-transport-services-to-crash/

https://social.technet.microsoft.com/Forums/exchange/en-US/fc23776c-bae4-4ca9-ad6d-4f8df880f47c/451-470-temporary-server-error-please-try-again-later-prx2?forum=exchangesvrsecuremessaging

https://gerhardwessels.wordpress.com/2013/05/06/451-4-7-0-temporary-server-error-please-try-again-later-prx2/

Damian,

Got it to work!

Here is what I did.... It seems exchange does not like having a internal and external DNS setting. I removed the external DNS setting from my IPV4 Adapter on the exchange server and removed the external setting from the Exchange ECP.

The second I did that the Queue disappeared. I am just waiting to receive the email or get a NDR from the two emails I sent it too. Been about 10 minutes still nothing....