We had a similar issue in May I can’t say for sure why, but we discovered that the IP’s of our two outgoing mail servers were listed on Backscatter.org
http://www.backscatterer.org/index.php?target=test
The give the option of fronting up $$ to be removed immediately or waiting for auto-delist in a month. Suffice to say we took the latter option and set an smtp fallback
Cheers
JT
--
Jodi Thomson
Network & Systems Engineer
Ph +64-6-8355800
Fax +64-6-8355811
Mob +64-21-903712
E-Mail jodi@team.waspnet.co.nz
From: nznog-bounces@list.waikato.ac.nz [mailto:nznog-bounces@list.waikato.ac.nz] On Behalf Of Steve Brorens
Sent: Thursday, 7 June 2012 2:14 p.m.
To: 'NZNOG Mailing List'
Subject: [nznog] Hotmail.com live.com blocking NZ
For all of this month we’re seeing a wide IP ranges – from several local ISPs - being blocked by the hotmail.com and live.com mail servers.
We understand that the ISPs concerned are working directly with Microsoft - anyone on this list able to give some feedback on progress?
- steve
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Steve Brorens
Systems Architect
CommArc Consulting Ltd
Mail: sjb@commarc.co.nz
Phone: 021 332289
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