Hi Experts,

Please i need assistance on how to sort out an issue that iam facing at present with the mail flow of external emails

I have 4 exchange servers running on version 2013 and more than 1000 client users who are using the mail service.

However, i have been getting more requests from clients that they have not been receiving mails recently especially external ones. Internally, everything works fine, sending and recieving seem to be no problem. The problem now is with sending & receiving external emails that seem to be block somewhere.

From the Queue Viewer(Exchange toolbox), i can see that under Delivery type option, most are showing DnsConnector Delivery with the STATUS as RETRY & CONNECTING. opening up one message properties(General tab) - sender address rejected: Domain not found;0;CN=internet connector....................................................

Also an error recieved showing message delay and/or DNS query failed with error Error Retry.

Before i forgot, adding on the that, i have realised that on the exhange admin center there are 2 alerts iam receiving promting me to renew my mail dns name(with assigned services-IMAP,POP,IIS &SMTP) which will expire on the 08/08/2015. please advise if this might be the cause or to do with settings on the send and receive connectors under Mail Flow.

Really need assistance on this

Thanks

Kedesh

A domain that's about to expire but hasn't yet expired is not the problem, so you can cross that off your list.

That message suggests that you don't have a properly configured reverse DNS record (PTR) in Internet DNS, you might be on a blacklist, you might not have a properly configured SPF record, a SMTP banner with a hostname that's different from your DNS entry, or something else of the sort that is causing the recipient to reject mail from you.

Thanks for the reply so whats the best method in which to be followed to have the above rectificed. Please could you provides step by step workable solution to address the issue.

await your assistance

Hi Kedesh,

Thank you for your question.

Did external flow have any problems in the former?

We could telnet port 25 of Exchange from external to check if it is successful. We could run Microsoft Remote Connectivity Analyzer by the following link to check if there are any errors:

https://testconnectivity.microsoft.com/

then we could run the following command to make sure all server components are active:

Get-ServerComponentState Identity <Servrername>

If there are any questions regarding this issue, please be free to let me know.

Best Regard,

Jim