CRM Email Rejections Caused by Missing DKIM and DMARC Settings

June 11, 2025

Missing DKIM signatures combined with strict DMARC policies caused CRM emails to bounce, leaving systems vulnerable to spoofing.

CRM Email Rejections Caused by Missing DKIM and DMARC Settings

I was recently reached out to by someone experiencing an email rejection issue in their CRM system. Nobody in their team could send emails because once they hit the send button, the email, instead of being sent, would change its status to 'bounced'. What a mystery lol 🤔

Turns out, their DMARC policy was set to 'reject' and the DKIM signatures were nowhere to be found. I expressed my admiration to the DMARC policy they had set and mentioned that getting those DKIM signatures in place would have the issue sorted.

And what next? Both me and the DMARC 'reject' were left in the dust & they swung open the doors to the world of spoofing with 'p=none'.

Can’t wait to see the 'problem-solving' skill added to their CV 🙃

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