I configured my server (Debian Jessie) and domain with DKIM. I installed OpenDKIM on my server, and followed this tutorial. I went to my domain provider, and set a new DNS TXT record for
"v=DKIM1; k=rsa; p=ThePublicKey"`
Where I got the key from
mail.txt, which was generated by the command:
opendkim-genkey -s mail -d example.com
I made sure that the OpenDKIM server is working, and that Postfix is signing the messages. However, I'm unable to find an unbiased way to check whether the emails sent from my server are signed properly.
By googling, I found this service, which gets me to send an email to it, and gives me a report on whether the signing is correct. However, it keeps saying that the signature is invalid in the end report:
SpamAssassin Score: 1.179 Message is NOT marked as spam Points breakdown: 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [URIs: example.com] 0.0 HTML_MESSAGE BODY: HTML included in message 0.3 HTML_IMAGE_ONLY_04 BODY: HTML: images with 0-400 bytes of words 0.7 MPART_ALT_DIFF BODY: HTML and text parts are different 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid 0.0 TVD_SPACE_RATIO No description available. 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid
Although it says in another part (at the DKIM Information, above that report) that it's valid. It says exacly:
Validating Signature result = pass
While in mxtoolbox, it doesn't show that I have any syntax problem in my DNS entry. It's able to parse the public key without problems.
What can I do to find the problem with my DKIM setup?