Question Your reverse DNS does not match with your sending domain.

[shogunswb]

I have a dedicated server with several domains but with the same problem on all domains.
Server hostname is anim8design.uk with a single IP 62.138.4.97 which is shared with all the domains.
rDNS resolves to anim8design.uk & DMARC, SFP & DKIM all pass when sending mail to Gmail, outlook etc yet the emails are always classed as spam.
Several DMARC checkers I have used say that the SPF & DKIM are not aligned with DMARC but I cannot figure out how to solve it.
Below is the error I got with mail-tester.com


Your IP address 62.138.4.97 is associated with the domain anim8design.uk.
Nevertheless your message appears to be sent from posterprint.co.
You may want to publish a pointer (PTR type) DNS record with a value of posterprint.co or use anim8design.uk as hostname in your mail software
Here are the tested values for this check:

• IP: 62.138.4.97
• HELO: posterprint.co
• rDNS: anim8design.uk

Any ideas very welcome
Thanks

 

[Dave W]

Looks like the hostname in Postfix is set to posterprint.co ?

Try Emails are sent with a wrong hostname in a sender address from a Plesk for Linux server with Postfix

 

[shogunswb]

Thanks for your reply but that doesn't appear to be the problem.
The Helo header in the email will be whatever domain I am sending from but the IP & rDNS will always be the same.
What I believe I need to do is somehow change the Helo to anim8design.uk for all the domains hosted on the server.

 

[Jeff@rackAID]

The error you see is what is known as Forward-Confirmed reverse DNS (FCrDNS). This basically means that the hostname's A record must match the reverse DNS (PTR) record for the IP.

While some legacy email service providers may use this and a few anti-spam solutions check this value, I do not find that it is very important. The last time I saw an explicit block due to this was for Craigslist, but hat was years ago.

With regards to Gmail, FCrDNS is not require for inbox placement. I do a lot of Gmail blacklist removal work, and even in the most serious cases of spamming, I don't worry about FCrDNS.

Since you cannot have multiple PTR records, there is no solution to this issue without some tradeoffs. If you want to attempt to fix it, you can set Plesk to send email's from the domain's IP address (Tools & Settings -> Mail). Then send a test email from a few domains. Examine the headers to see what server name is being used in the Received from line.

Setup your PTR record to match the received from line.

In regards to Inbox placement, I recommend you enroll in Gmail's Postmaster Tools. See if you have a low IP or domain reputation. If your DMARC, DKIM, & SPF are passing, then low IP/domain reputation is the most likely reason for inbox placement.

If Gmail users are not flagging your emails as spam, your sending reputation will improve - and with it your inbox placement rates.

 

[trialotto]

@shogunswb

Both @Dave W and @Jeff@rackAID have introduced valid arguments - but that might not paint the entire picture.

The essential problem here is that Plesk by default is configured in such a way that mails send from a domain are send from that domain - rather obvious, but it is impractical.

The confusing part here is that other mail servers or services might do a reverse DNS check - they have a look at the PTR record.

It is not very easy to configure a PTR record properly and sometimes it even is not possible.

The root cause of the problem here is : external mail servers or services doing an old-fashioned reverse DNS check.

After all, to solve that root cause of the problem would imply that you should have one PTR record for each domain that you send mail from - impossible, not practical at all.

In short, the ones to blame are the sysadmins using reverse DNS checks.

One could argue that one should still want to solve the issue at hand, but I am not a fan of that argument - there is always a very odd configurations somewhere on one of the many, many receiving mail servers : one can never get a perfect configuration, since other servers are mostly not configured properly (why care about solving their issues??).

One could argue to use dedicated services like SendGrid - I am a fan of SendGrid, but not a fan of this argument : again, there is no weapon or solution for issues that are in fact originating from bad configuration on other mail servers.

In summary, there is not much one can do - unless Plesk changes mail configuration drastically OR other people stop using reverse DNS checks.

Hope the above explains a bit.

Kind regards......

PS Please note that mail entering spam folders in Gmail or Outlook is not a problem related to Plesk - it is a problem associated with Outlook (the mail client as a whole) or with Gmail (the filters that Gmail uses).

PS2 You should use telnet commands (from another server than the server on which the mail servers of your domains are residing) to perform a proper and elaborate analysis of your problem - your current post is not providing enough information. Nevertheless, I am pretty sure that you telnet your way into the various mail servers and send mail without any problem, unless the receiving mail server is doing a reverse DNS check. In that case, a mail send with a from address identical to the hostname will probably not result in any problem, whereas other from addresses will cause your current issue to reoccur. Again, the root cause of the problem is the rDNS check.

 

[StewartMorrisonv]

Well, i have faced a really similar issue to be honest. Had no idea about how to fix it. I tried almost everything i could, i mean everything i knew. However, it was the same thing every single time. At last, a friend of mine told me to try a very simple trick. It was so simple and easy, that i just don't understand why i didn't think about it before. He told me to try and change my ip address ( to buy a great proxy) . He told me about the one from Residential proxies - IPRoyal.com. And you know what, it actually worked out.

 

[Bitpalast]

Well, i have faced a really similar issue to be honest. Had no idea about how to fix it.

First thing to check is that in Tools & Settings > Mailserver you have selected "Send from domain IP addresses" for "Outgoing Mail Mode".

 

[shogunswb]

Well, i have faced a really similar issue to be honest. Had no idea about how to fix it.

If I remember correctly the problem was with the hosting accounts I held with my hosting company.

We have a shared hosting account into which all our domains go then I redirect the dns of several of them to our dedicated server so that they are hosted on there.

The problem was that when the rdns was checked it was hitting the shared hosting first causing the problem. I then discovered from the hosting company that when I redirect the dns onto the dedicated server the domain is still hosted on the shared account & marked as a Parked Domain.

To rectify the problem I had to go to the parked domain & change the NAMESERVERS over to the dedicated server name ie NS1.yourservername.com, NS2.yourservername.com

After that had propagated things started to get easier. All I had to do then was check my IP wasn't blacklisted anywhere, tweek the DMARC, SPF & DKIM & then plead with Microsoft that after 3 years they had no reason to be junking legitimate mail sent from my server.

If you have any hair left after sorting it all out you did better than me.