Any help much appreciated on this…

I have a website up and running, and email associated with it. Off the back of something I read on STW, the website is hosted by a different hosting company (Hostwinds) than the one through which it’s registered (Namecheap). Due to the different solutions they offer, the email is hosted by the registration company (Namecheap), not the company that hosts the website. It’s not ideal, but it works, mostly.

The problem is my outbound email is falling foul of spam filters on DKIM – apparently it has 2 identical DKIM signatures (where there should only be 1), and so is seen as spam. Going into cPanel, there is only one DKIM signature applied, it just seems that each email passes through it twice (or something), possibly as a result of the convoluted email/ domain hosting/ registration setup.

Thoughts/ solutions?

What happens if you remove that signature? I’m really punting here but maybe you’re doing something manually that’s already being done automatically?

Do you get NDRs? Looking at the email header might provide some insight. There’s online tools to help you decipher them now (back in my day, kids of today, get orf my lawn etc).

DKIM uses DNS entries to verify that you’re the owner of the domain. I don’t think that the different providers should make any difference to anything here so long as the public key held in DNS matches the signature key in the message header?

I would be looking at the A record and MX record for the domain and any subdomains like www. and mail. It may be that both your hosting providers have set up DNS entries that overlap – although I don’t see why that would result in two DKIM signatures, unless one server is acting as smarthost and forwarding mail through the other? Try sending an email to another account and track it through the headers.

I had problems with hotmail servers because they were attempting to send incoming mail to the IP defined in the A record rather than the MX – the problem being that the A record pointed to my web host, and I didn’t have an email account on that server, so it bounced them.

Hmm… thank you, some good points. I’ll investigate and reply here 🙂

I find that this will often give a clue as to what’s wrong.

If the domain associated with the email address differs from the originating smtp domain – then spam filters might flag that. I had similar with my Easily (manage my domains) and Plusnet (manage my email) setup, the following DNS entry sorted it – might be the same for you?

(Type) (Name) (Value)
TXT @ “v=spf1 mx a include:plus.net”

Thanks for all the helpful feedback. Some exploration has uncovered… I’m not sure what.

SPF is up and working fine, at least. I’ve deleted the DKIM record in the DNS record, and left it for 24 hours to propagate. My regular mail deliverability testing app still shows email being sent with 2 (identical) DKIM records attached; but MX toolbox says there’s no DKIM record attached at all.

I’ve now re-enabled DKIM, will give it a while and check the email deliverability again.