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Exchange 2007 421 4.3.2 Service not available, closing transmission channel

Hi,

Just switch ISP and having issues with mail flow with exchange 2007
when sending an email to the domain I receive a Email Delivery Warning 4.3.2 Service not available, closing transmission channel

Regards

Valentina Perez

Hi Ben,

You need to check if you have backpressure. Do you have any events between 15000-15010?

Regards
Valentina

Zaheer Iqbal

is this issues with outgoing mails or incoming or both ?

Ben S

ASKER

Hi

No events in the events viewer between 15000-15010.
outgoing is working but taking longer than normal to receive, around 15 minutes.

Regards,
Ben

Ben S

ASKER

from the Microsoft connection test

The Microsoft Connectivity Analyzer failed to test inbound SMTP mail flow.
 	
	Additional Details
 	
Elapsed Time: 584 ms.
 	
	Test Steps
 	
	Attempting to retrieve DNS MX records for domain 'b.co.uk'.
 	One or more MX records were successfully retrieved from DNS.
 	
	Additional Details
 	
MX Records Host remote.b.co.uk, Preference 5
Elapsed Time: 16 ms.
	Testing Mail Exchanger remote.b.co.uk.
 	One or more SMTP tests failed for this Mail Exchanger.
 	
	Additional Details
 	
Elapsed Time: 567 ms.
 	
	Test Steps
 	
	Attempting to resolve the host name remote.b.co.uk in DNS.
 	The host name resolved successfully.
 	
	Additional Details
 	
IP addresses returned: 
Elapsed Time: 353 ms.
	Testing TCP port 25 on host remote.b.co.uk to ensure it's listening and open.
 	The port was opened successfully.
 	
	Additional Details
 	
Banner received: 421 4.3.2 Service not available, closing transmission channel
Elapsed Time: 140 ms.
	Analyzing SMTP Capabilities for server remote.b.co.uk:25
 	The test passed with some warnings encountered. Please expand the additional details.
 	
	Additional Details
 	
Unabled to determine SMTP capabilities. Reason: Unexpected SMTP server response. Expected: 220, actual: 421, whole response: 421 4.3.2 Service not available, closing transmission channel
Elapsed Time: 38 ms.
	Attempting to send a test email message to administrator@b.co.uk using MX remote.b.co.uk.
 	Delivery of the test email message failed.
 	
	Additional Details
 	
The server returned status code 421 - Service not available, closing transmission channel. The server response was: 4.3.2 Service not available, closing transmission channel
Exception details:
Message: Service not available, closing transmission channel. The server response was: 4.3.2 Service not available, closing transmission channel
Type: System.Net.Mail.SmtpException
Stack trace:
at System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at Microsoft.Exchange.Tools.ExRca.Tests.SmtpMessageTest.PerformTestReally()
Elapsed Time: 36 ms.

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Zaheer Iqbal

Not sure of your configuration and setup please check your receive connectors on the CAS.

Zaheer Iqbal

Have you updated your MX record to new ISP IP.

Ben S

ASKER

I have updated the mx record with DNS provided and added the new IP to the receive connector remote IP, is this correct?

Zaheer Iqbal

Try MXToolbox.com and see what that comes back does it come back with the correct IP ?

ASKER CERTIFIED SOLUTION

Zaheer Iqbal

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Ben S

ASKER

Just figured out the issue thanks for the help,

I just added 0.0.0.0-255.255.255.255 to the internet receive connector

Ben S

ASKER

should this be 0.0.0.0-255.255.255.255 or just the public IP of the exchange server?