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Introduction

This error occurs when your domain is missing the required DKIM CNAME record for JetEmail to sign your outbound mail.

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Example Error Message

Here’s what this error can look like: 
550 DKIM validation failed: Required CNAME record jetemail._domainkey.domain.com not found.

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What is DKIM?

DKIM (DomainKeys Identified Mail) attaches a cryptographic signature to each email so recipients can verify that the message was authorized by your domain and wasn’t altered in transit.

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Why You’re Seeing This

  • Your domain has not published the required DKIM CNAME used by JetEmail to sign messages on your behalf; or
  • You are relaying through a smarthost and your upstream system is not DKIM-signing messages (or the signature is being removed), causing our service to require your DKIM CNAME instead.

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How to Fix

If you want JetEmail to DKIM-sign your messages, publish this CNAME in your DNS: 
Name: dkim._domainkey.{your-domain}
Value: dkim.jetsmtp.net
Replace {your-domain} with your actual domain. Example: 
dkim._domainkey.example.com CNAME dkim.jetsmtp.net
If you relay through a smarthost and already DKIM-sign mail upstream, you should not see this error. If you do, your messages are not being DKIM-signed (or the signature isn’t preserved). Ensure your MTA is signing outbound mail correctly, or alternatively publish the CNAME above so JetEmail can sign.

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Verification

  • Allow up to 24 hours for DNS propagation
  • Verify your DKIM setup with your preferred DNS/DKIM checker
  • Retry sending once DNS has updated
For broader setup details, see our Email Authentication Requirements and DMARC guidance.