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Exchange 2013 SMTP inbound is taking up to several hours to receive emails. Is there a way to optimize the speed of incoming mail?

Last Modified: 2014-09-02

Ive put an Exchange 2013 intallation in 3 weeks ago. The setup is all on one server which shares AD and DNS. There is a split domain scenario with .local and .com in the internal DNS. Messages tend to send out instantly but outside mail takes awhile. We had to move the zone file to go daddy a week ago ant the problems have increased. The MX record is set to * and associated to the WAN ip of the server. Is there anyway to test for incorrectness or optimize the server for quicker reception of mail? I tried adding an SPR record. Also we are getting tons of spam now. Is the internal filter in Exchange sufficient. Any help would be a life saver.
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Zephyr ICTCloud Architect

For starters I'd run the checks using http://mxtoolbox.com/ and check DNS setup of your domain with http://www.dnsinspect.com/. Post any issues detected (sanitize the domain name if needed).

This will give us some ideas on where to help out.


I ran the exchange analyzer and it was all checks. Mxtoobox generated a delay error. I rebooted the server and now am getting Attempting to send a test email message to thartdegen@hymeldavis.com using MX mail.hymeldavis.com.
  Delivery of the test email message failed.
 Additional Details
The server returned status code 451 - Error in processing. The server response was: 4.7.0 Temporary server error. Please try again later. PRX2
Exception details:
Message: Error in processing. The server response was: 4.7.0 Temporary server error. Please try again later. PRX2
Type: System.Net.Mail.SmtpException
Stack trace:
 at System.Net.Mail.DataStopCommand.CheckResponse(SmtpStatusCode statusCode, String serverResponse)
 at System.Net.Mail.DataStopCommand.Send(SmtpConnection conn)
 at System.Net.Mail.SmtpClient.Send(MailMessage message)
 at Microsoft.Exchange.Tools.ExRca.Tests.SmtpMessageTest.PerformTestReally()

Elapsed Time: 605 ms.
Zephyr ICTCloud Architect

So hymeldavis.com is your domain name right? DNS wise it's looking ok, spf missing and reverse DNS mismatch, nothing major.

Can you run this command on your mail server:

get-ReceiveConnector | select name,tarpitinterval
Most Valuable Expert 2014

Unless you have changed the tarpit interval the default is usually fine.
What else is on the server, as my instinct is this is outside of Exchange. If you have antivirus on the server, does it have the correct exclusions for Exchange configured within?



No AV, just AD and DNS. I removed an offline backup from the server prior to this error but can't identify it as the prime reason for the fail as the mail has been ultra slow and I got a similar error to this from sending on an outside email domain.
Zephyr ICTCloud Architect

How is the network configured on this host? Gateway correct? Internal DNS server(s)? ... Routing ok?
We'll need more info to pinpoint the possible issue.
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Well I set the tarpitting to 0 and the time went down significantly on the analyzer. Still Im going to monitor it this evening as Im not 100% confident that it fixed the issue.
Most Valuable Expert 2014

Do you have something between Exchange and the internet?
I have never had to change tarpit time, so if you have seen a change by doing so that would suggest something is interfering. Tarpit shouldn't affect the day to day operation of email delivery.


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