This refers to Exchange Online Protection (EOP, aka the filtering arm of Office 
355, not Hotmail/outlook.com).

We don’t respect p=reject for multiple reasons:

1. If we did, nobody would ever be able to get their mailing list traffic from 
p=reject domains unless the list operated as a pure forwarder, and many of them 
don’t
2. Plenty of senders mess up their DMARC records, or send with misaligned 
traffic, and we don’t want to reject those as it gives the receiver no way to 
get them
3. We have about 15% of our customers who do complex routing which puts other 
mail servers in front of ours; or route through, then out of our service and 
back again, and break SPF, DKIM, DMARC and would otherwise be rejected

If EOP overrides the p=reject action, this is indicated in the headers by 
putting an oreject into the action=<action> field and then marking as spam 
(setting SCL 9, the highest spam confidence level). For example:

dmarc=fail action=oreject
http://blogs.msdn.com/b/tzink/archive/2014/12/03/using-dmarc-in-office-365.aspx

-- Terry

From: dmarc-discuss [mailto:[email protected]] On Behalf Of Larry 
Finch via dmarc-discuss
Sent: Wednesday, November 25, 2015 9:00 AM
To: Nicolás via dmarc-discuss
Subject: Re: [dmarc-discuss] Office 365 does not repect dmarc rejection policy!?


On Nov 25, 2015, at 7:14 AM, Jacob Evans via dmarc-discuss 
<[email protected]<mailto:[email protected]>> wrote:

Here's a snip of the message header, it looks like Microsoft has opted to 
implement DMARC, but not respect it.

Authentication-Results: spf=pass (sender IP is 209.141.51.12)
 smtp.mailfrom=jacobdevans.com<http://jacobdevans.com>; 
appalachiatech.com<http://appalachiatech.com>; dkim=none (message not
 signed) header.d=none;appalachiatech.com<http://appalachiatech.com>; 
dmarc=fail action=oreject
 header.from=appalachiatech.com<http://appalachiatech.com>;

Do we expect Microsoft to respect it or is this another lost battle to the 
software giant?


Google doesn’t respect it either. Which is a good thing.

Larry
--
Larry Finch
[email protected]<mailto:[email protected]>



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