Need to edge out the competition for your dream job? Train for certifications today.
Experts Exchange Solution brought to you by
"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.
Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.
The Microsoft Connectivity Analyzer failed to test inbound SMTP mail flow.
Elapsed Time: 584 ms.
Attempting to retrieve DNS MX records for domain 'b.co.uk'.
One or more MX records were successfully retrieved from DNS.
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.
Elapsed Time: 567 ms.
Attempting to resolve the host name remote.b.co.uk in DNS.
The host name resolved successfully.
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.
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.
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 email@example.com using MX remote.b.co.uk.
Delivery of the test email message failed.
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
Message: Service not available, closing transmission channel. The server response was: 4.3.2 Service not available, closing transmission channel
at System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
Elapsed Time: 36 ms.
Open in new window
Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.
From novice to tech pro — start learning today.
Premium members can enroll in this course at no extra cost.
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.
Please enter a first name
Please enter a last name
Must be at least 4 characters long.
Join and Comment