Issues sending to Google and Microsoft
I'm helping my father (a plusnet customer) overcome an issue he is experiencing when sending email to some of the larger email providers. It appears the SMTP server that is sending out his mail has been blacklisted from some providers leaving delivered mail in the spam folders of the recipients. I should note that this only occurs when sending through his outlook client as when sending through the web mail interaface all is well. I have checked his SMTP Outlook settings and all seems to be well (relay.plus.net: 587 etc..).
The mail appears to be proxied via avasout02.plus.net (184.108.40.206) and this is the IP which is failing google's spam check score. He has contacted plusnet customer services but not much use unfortunately as they indicated it may be to do with his individual IP address which could be black listed, which is not correct as this is the IP address of a plusnet server and just to double check I sent mail through a VPN which also suffered the same fate. They also said that (which I know is true) that google will eventually remove the server from the blacklist but this has been going on a number of months now with no sign of the server returning to the white list!
I wonder if the problem is due to the sender's domain being tiscali.co.uk as it failed on the SPF check citing an issue with the domain. DMARC check also failed but I've not come across this before.
Any help would be greatly appreciated, perhaps @bobpullen can help?!
Below is the conversation between the two mail servers if it may any use.
Received: by 10.28.109.2 with SMTP id i2csp778384wmc; Thu, 20 Oct 2016 03:19:33 -0700 (PDT) X-Received: by 10.194.143.47 with SMTP id sb15mr7051024wjb.110.1476958773744; Thu, 20 Oct 2016 03:19:33 -0700 (PDT) Return-Path: <email@example.com> Received: from avasout02.plus.net (avasout02.plus.net. [220.127.116.11]) by mx.google.com with ESMTPS id s5si60421811wjo.284.2016.10.20.03.19.33 for <firstname.lastname@example.org> (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 20 Oct 2016 03:19:33 -0700 (PDT) Received-SPF: fail (google.com: domain of email@example.com does not designate 18.104.22.168 as permitted sender) client-ip=22.214.171.124; Authentication-Results: mx.google.com; spf=fail (google.com: domain of firstname.lastname@example.org does not designate 126.96.36.199 as permitted sender) email@example.com; dmarc=fail (p=QUARANTINE dis=QUARANTINE) header.from=tiscali.co.uk Received: from HomePC ([188.8.131.52]) by avasout02 with smtp id xmKY1t0030YTCjS01mKZlN; Thu, 20 Oct 2016 11:19:33 +0100 X-CM-Score: 0.00 X-CNFS-Analysis: v=2.2 cv=G/5eKJs5 c=1 sm=1 tr=0 a=LuK6y61l2DEeFyoFiWaXiQ==:117 a=LuK6y61l2DEeFyoFiWaXiQ==:17 a=MKtGQD3n3ToA:10 a=dik7HMQjudEA:10 a=ZZnuYtJkoWoA:10 a=DAwyPP_o2Byb1YXLmDAA:9 a=c4jg8kwGBT3RChCC0hkA:9 a=CjuIK1q_8ugA:10 a=yMhMjlubAAAA:8 a=SSmOFEACAAAA:8 a=gKO2Hq4RSVkA:10 a=UiCQ7L4-1S4A:10 a=hTZeC7Yk6K0A:10 a=frz4AuCg-hUA:10 a=BKKCjISod1eDJeS0ORpz:22 a=zjWhRoSqWz9hl55Hdlzg:22
Re: Issues sending to Google and Microsoft
I wonder if the problem is due to the sender's domain being tiscali.co.uk as it failed on the SPF check citing an issue with the domain. DMARC check also failed but I've not come across this before...
That's almost certainly the problem. The domain tiscali.co.uk has an SPF record as follows:
v=spf1 mx a ip4:184.108.40.206/26 ip4:220.127.116.11/26 ip4:18.104.22.168/26 ip4:22.214.171.124/26 -all
This is something governed by Tiscali themselves and what it's basically saying is - "Email from tiscali.co.uk addresses should only ever be sent through email servers that belong to the following IP ranges - 126.96.36.199/26, 188.8.131.52/26, 184.108.40.206/26 or 220.127.116.11/26. If you receive an email from this domain that's been sent via any other email server then you should treat it as suspicious or reject it"
Google's servers are seeing that the email has been sent via Plusnet, rather than one of Tiscali's designated servers, and is therefore 'spamming' it.
@The solution would be to use Tiscali's outbound server (if possible), or avoid sending email from @tiscali.co.uk addresses.
Plusnet Product Team
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