Hi Chris, Although rare, this isn't unusual. For some reason Microsoft considered there's an issue. In a similar case I had recently, I couldn't say that " part of their network is on our block list "* is untrue. We have some IPs blocked, as seen on SNDS, and some on the same range as the IPs that generated these replies. However, those specific IPs had a pretty fine traffic. So these IPs were getting rejection because other IPs in the network (range?) are also blocked, but despite being rejected, those weren't blocked. These 2 IPs (with the same fine traffic) generated rejections (not the plenty of other neighbor IPs in the same situation of "part of network is on block list"), they were submitted together to the Support, first answer was "we see no problem on one and the other has been mitigated". The next day, the "no problem" one was still rejecting, so I pushed back to the Support, and they mitigated as well. Case closed!
There's mystery (or dark magic) going on in Outlook.com. But after a few back and forth with the Support, they've been mitigated, and back to normal. So honestly at this point, I let the "but why" go! * I believe that being on Microsoft's "block list" isn't necessarily about the blocked IPs we can see on SNDS -- Benjamin -----Original Message----- From: mailop <mailop-boun...@mailop.org> On Behalf Of Chris Malton (Delta V) Sent: mardi 11 décembre 2018 08:42 To: Michael Wise <michael.w...@microsoft.com>; mailop@mailop.org Subject: Re: [mailop] Outlook/Hotmail/etc rejecting email (but not Office 365) On 11/12/2018 00:11, Michael Wise via mailop wrote: > Looks like Mitigation was applied, but it's possible that the /24 had some > bad tenants previously? I have a hunch it was allocated before, I'm just curious why it's been working for 2-3 months, and then suddenly stopped between Saturday night and this morning. > We don't provide support thru MailOp, only via the Support webform, which it > seems you have already discovered. Understandable Michael - was just curious if anyone else could see anything I'd obviously missed. Your Deliverability Support Team have been in touch off the back of that form and things now seem to be working again. Many thanks for any work you did behind the scenes to get this in front of the right people. Regards, Chris Malton -- Delta V Technologies Limited 03333 402 406 www.deltav-tech.co.uk Office: 17 Elm Close, Southampton, SO16 7DT Company No. 11006104 Registered in England and Wales _______________________________________________ mailop mailing list mailop@mailop.org https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop _______________________________________________ mailop mailing list mailop@mailop.org https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop
