Level 1: Cadet

Emails from 4G services using an office 365 email are bouncing.



We are having an issue where when roaming on the telstra 4G network (eg not in the office wifi) we are getting bounced emails from anyone that is using office 365 at the moment.


Upon looking into this further I have found that the source IP's telstra are using are here:




Looks like the whole /12 is listed. 


We are sending emails using an office 365 account (microsoft direct) to anyone that uses Spamhaus filtering (most if not all of office 365) are bouncing. 


I have spoken to Telstra Support on a number of occasions but no one seems to understand what is going on. I also requested to change the IP address allocations of the 4g phones but that cant be done either. 


When the phones move into Wifi then there is no issue, the issue only appears when we are mobile (which is kind of the whole point of remote / mobile workers), which is how we limited this to the telstra IP range


So it would be great if telstra could fix this, everyone I have spoken to so far have no idea on to who to even direct this to.





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Level 1: Cadet

Re: Emails from 4G services using an office 365 email are bouncing.

The bounce message is

"Remote Server returned '550 5.7.501 Service unavailable, Client host blocked using Spamhaus. To request removal from this list see http://www.spamhaus.org/lookup.lasso (AS16042849)'"
Telstra (Retired)
Telstra (Retired)

Re: Emails from 4G services using an office 365 email are bouncing.


I have sent you a Private Message regarding this issue, thanks.

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