Level 1: Cadet

Sending emails to Telstra/Bigpond domains being blocked



I have a customer who is a not for profit business who has many club members with @bigpond.com, @bigpond.net.au, @bigpond.com.au and @telstra.com addresses. We have recently been getting errors sending to these addresses. The main error is: 451 4.4.0 Primary target IP address responded with: "421 Connection refused. IB113."


I have our Exchange 2010 server setup with reverse lookup and I have checked Spamhaus/mxtoolbox to see if we are blacklisted and we are not being blacklisted on any major blacklist. Our internet connection is with Telstra Internet Direct and it is a dedicated fibre line. Is there any process I can go through with Telstra to get our domain and IP cleared? 

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Level 25: The Singularity
Level 25: The Singularity

Re: Sending emails to Telstra/Bigpond domains being blocked

The IB113 part of the message would indicate that the IP address has sent too many messages to invalid recipients and has been blocked. This is normally a temporary error and should clear itself within 24 hours.


As it is the IP address that the problem is recorded against, it may not be your client's emails that are causing the problem if it is an IP address shared with others.

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