DKIM Invalid.

[nedova]

Hello!

When my emails were going to spam, I decided to take a spam test with mail-tester.com. It said that my DKIM signature was invalid. I used the DKIM signature from DirectAdmin itself. Is there any way to regenerate it?

Kind Regards
comfyy,
Nedova Network.

 

[ikkeben]

Try first some online dkim checks test and more

Mimecast DKIM Check

Mimecast DKIM Check provides full visibility into all email senders using your domain. Use our DKIM record checker to identify legitimate vs fraudulent senders.

www.dmarcanalyzer.com

Then look into docs help and howto DA stuff yes or no for domain or hostname ... and so on

Take care if asking support to post also versions used and os and and and some config / setting how.. of the box

 

[Richard G]

Is there any way to regenerate it?

Yes.
First remove it from the DNS records, then go via SSH:
cd /usr/local/directadmin/scripts ./dkim_create.sh domain.com

However, this will probably create the same DKIM record. So best is to do what @ikkeben wrote, check with dmarcanalyzer if it's correct.
Could be little mistake with mail-tester.com also. So better check elsewhere too.

You can also do this test, which gives more output than mail-tester does, and often shows causes of issues:

Mail Tester: Free Email Spam Checker - Email Deliverability Tester

Use our Mail Tester to test email. Get 3 Free Spam Tests to check your Email Deliverability and spam score with our free email spam checker.

www.mailgenius.com

 

[nedova]

okay, weirdly, the website which @ikkeben wrote says my website's DKIM record is indeed valid. However the website which @Richard G gave says my DKIM has errors. The following are the error outputted by mailgenius

(-2 points) Your email is not properly authenticated with DKIM.​

(-1 points) The DKIM signature is not from the author's or envelope-from domain.​

How can I fix it?

 

[Richard G]

It's not that weird as you think.
The site @ikkeben is pointing to checks your DKIM DNS record.
But there is a difference with having a correct DKIM record in DNS and information the mailserver gets/uses when sending mail.

Seems when sending mail, something is off, it looks like another domain is used as the envelope-from domain for some reason, so that is where you might have to look why this is happening.

For example, if you're using an external DNS, is the dkim record copied correctly.
Try sending a mail from Roundcube and see if you also have these numbers then on the mailgenius test site.

 

[nedova]

Yup. Sending from Roundcube worked. That one's got valid DKIM. Although I am scratching my head on why sending from Thunderbird said that DKIM wasn't valid.

 

[Richard G]

Oh sending from Thunderbird... that might cause the same issue I once found here somewhere with Outlook.
Had something to do with 7 and 8 bit encoding... I'll have a look.

... ah found it... took me some time. It's seems the same as what I found here:

DKIM signature valid or not valid?

Hi, I have successfully installed DKIM some weeks ago. Ran some tests and DKIM are valid, however not on dkimvalidator.com and Hotmail/Office 365 receiver. Let me explain. We send a mail to a client with a PDF file of his order. According to Google the DKIM, SPF and DMARC is valid (pass)...

forum.directadmin.com

So if I'm not mistaken, you should be able to fix that by changing the "Content transfer encoding" setting. I don't know what you've got there at the moment.

Maybe you can find some usefull info here:

Thunderbird can no longer send with 7bit Content-Transfer-Encoding, since version 55.0b2 | Thunderbird Support Forum | Mozilla Support

support.mozilla.org

 

[nedova]

Thanks!