What to do when DKIM record is configured but emails are not DKIM signed?

Summary

When DKIM is configured but emails aren't being signed, the issue often stems from a combination of configuration errors, ESP settings, and DNS propagation problems. Key areas to investigate include ensuring the ESP has the private DKIM key and has activated signing, that the correct selector is used and matches in both the DNS record and email headers, and that DNS records have fully propagated. Checking email headers for a DKIM signature confirms whether signing is occurring. Additionally, the sender domain configuration must match the DKIM record's domain. If issues persist, contacting ESP support is advised, and it's essential to not assume the ESP is signing emails; active verification is needed.

Key findings

  • ESP Configuration & Activation: Verify that the ESP has the private DKIM key and that DKIM signing is activated in the ESP's settings.
  • Selector Matching & DNS: Ensure the correct selector is used and that it matches in both the DNS record and the email headers. DNS records must be accurate.
  • DNS Propagation: Confirm that the DNS records have fully propagated and are accessible across global DNS servers.
  • Header Verification: Check email headers for the DKIM-Signature header to verify that signing is actually occurring.
  • Domain Configuration: Make sure the sender domain configuration in the email platform matches the domain for which the DKIM record is created.

Key considerations

  • Active Verification Needed: Do not assume that the ESP is signing emails; active verification is necessary.
  • ESP Support Consultation: Contact the ESP support team to assist in diagnosing and resolving any DKIM-related issues.
  • Review Previous Settings: If migrated from another vendor, it's possible the DKIM record is for a previous vendor.
  • Use Online Tools: Utilize online tools to check DNS record propagation and the validity of the DKIM configuration.

What email marketers say
10Marketer opinions

When a DKIM record is configured but emails are not being signed, several potential issues need to be investigated. These include verifying that the email service provider (ESP) is configured to sign outgoing emails, that DKIM signing is activated within the ESP's settings, and that DNS records have fully propagated. Additionally, the correct sender domain configuration needs to be ensured within the email platform, and the email headers need to be checked to confirm the presence and validity of the DKIM signature. Contacting the ESP support team can also assist in diagnosing the issue.

Key opinions

  • ESP Configuration: Ensure your ESP is properly configured to sign emails with DKIM.
  • DKIM Activation: Verify that DKIM signing is activated within your ESP's settings.
  • DNS Propagation: Confirm that DNS records have fully propagated and are accessible.
  • Sender Domain: Check that the sender domain configuration in your email platform matches the domain for which the DKIM record is created.
  • Header Verification: Examine email headers to confirm the presence and validity of the DKIM signature.

Key considerations

  • ESP Consultation: Contact your ESP support team for assistance in diagnosing and resolving DKIM issues.
  • Record Review: Review the DKIM record and ensure the selector is correct.
  • Raw Source: Examine the raw source of the email to confirm the DKIM signature is being added.
  • Old Record: The existing DKIM record could be for a previous vendor - and will need updating.
Marketer view

Email marketer from StackExchange shares that the issue could stem from domain settings not propagated correctly. Ensure the DNS records have fully propagated and are accessible from all global DNS servers.

December 2023 - StackExchange
Marketer view

Marketer from Email Geeks responds saying that if “your provider” refers to your ESP, you should discuss getting DKIM signatures in your messages with them.

August 2022 - Email Geeks
Marketer view

Email marketer from Email Geeks shares that you need to ensure you've turned on the "activation" for DKIM signing from your ESP portal once you got your public key in DNS.

December 2021 - Email Geeks
Marketer view

Email marketer from Email Marketing Forum recommends contacting your Email Service Provider's (ESP) support team. They can often diagnose and resolve issues related to DKIM signing on their end.

November 2024 - Email Marketing Forum
Marketer view

Email marketer from StackOverflow suggests examining an outgoing email's raw source to confirm whether the DKIM signature is being added. This helps identify if the issue is on the sending side.

February 2024 - StackOverflow
Marketer view

Email marketer from Email Deliverability Forum recommends checking the sender domain configuration in your email platform. It must match the domain for which the DKIM record is created.

September 2023 - Email Deliverability Forum
Marketer view

Email marketer from Email Geeks explains that it may be the earlier email vendor's DKIM record and to contact your current vendor and say that you'd like to sign DKIM on your sender domain and they will help you with the next steps.

September 2023 - Email Geeks
Marketer view

Email marketer from StackOverflow recommends verifying that the sending server is actually configured to use the DKIM key for signing outbound emails. It's possible the record is present but not actively used by the mail server.

July 2023 - StackOverflow
Marketer view

Email marketer from Super User suggests checking the email headers to see if the DKIM signature is present and valid. The header will indicate if DKIM signing was attempted and whether it passed or failed.

November 2024 - Super User
Marketer view

Email marketer from Reddit highlights that you might need to specifically activate DKIM signing in your email sending platform's settings. Some platforms require you to enable it even after the DNS records are in place.

July 2023 - Reddit

What the experts say
4Expert opinions

When a DKIM record is configured, but emails are not being signed, it's crucial to verify that your Email Service Provider (ESP) has received the private key and enabled signing. DKIM involves two key components: a public key in your DNS record and a private key used by the mail server to sign emails. You should actively check the email headers for the DKIM-Signature to confirm signing is occurring, not assumed. Finally, ensure the selector in your DKIM record precisely matches the one used in your email headers; any mismatch will result in verification failure.

Key opinions

  • Private Key and ESP: Confirm the ESP has the private DKIM key and has enabled signing.
  • DKIM Components: DKIM consists of a public key in DNS and a private key used by the mail server.
  • Header Verification: Check email headers for the DKIM-Signature to confirm signing is happening.
  • Selector Matching: Ensure the DKIM selector in your record matches the one in the email headers.

Key considerations

  • Active Verification: Don't assume the ESP is signing; actively verify.
  • Key Setup: Proper key exchange and configuration are essential for DKIM to function.
  • Technical Expertise: If uncertain, seek expert help to review DKIM setup and troubleshoot.
Expert view

Expert from Email Geeks asks if the private key was sent to your ESP and if they turned on signing.

February 2022 - Email Geeks
Expert view

Expert from Wordtothewise responds that you should confirm that the selector in your DKIM record matches the selector used in your email headers. A mismatch will cause the verification to fail.

January 2024 - Wordtothewise
Expert view

Expert from Spamresource explains that one needs to verify that the signing is actually happening on your emails and not just assume the ESP is doing it. Check the headers to see if the DKIM-Signature header is present.

March 2025 - Spamresource
Expert view

Expert from Email Geeks explains there are two parts to DKIM: the record within your DNS (with the public key), and the mail server sending your mail has to be configured to sign the mail (with the private key).

December 2024 - Email Geeks

What the documentation says
5Technical articles

When DKIM is configured, but emails are not signed, troubleshooting involves several key steps. First, ensure DKIM is enabled for the domain and that the correct selector is being used. Verify the accuracy of the DNS record and that the private key on the mail server matches the public key in DNS. Additionally, confirm the email content hasn't been altered in transit. Check the DKIM keys are published correctly and ensure DNS records have propagated globally, as this can take time. An incorrect selector in the email configuration is a common cause, so double-check this as well.

Key findings

  • DKIM Enabled: Confirm that DKIM is enabled for the domain.
  • Selector Verification: Verify that the correct selector is being used in the email configuration and that it matches the selector in the DKIM DNS record.
  • Key Matching: Ensure the private key on the mail server matches the public key in DNS.
  • DNS Record Accuracy: Check the DNS record for accuracy and proper key length configuration.
  • DNS Propagation: Allow sufficient time for DNS records to propagate globally.

Key considerations

  • Troubleshooting Tools: Use online tools to check DNS record propagation and DKIM configuration.
  • Transit Integrity: Consider whether email content is being altered in transit, affecting DKIM validation.
  • Configuration Review: Regularly review DKIM configuration to prevent issues.
Technical article

Documentation from Microsoft shares the importance of verifying that the DKIM keys are published correctly by checking the DNS records and ensuring the selector matches the key length configured.

October 2022 - Microsoft
Technical article

Documentation from Google explains that if DKIM signing fails, start by checking if DKIM is enabled for the domain, verifying that the correct selector is being used and confirming that the private key is correctly configured on the sending server.

April 2022 - Google
Technical article

Documentation from MailChannels explains that a common cause is using an incorrect selector in your email configuration. Double-check that the selector used by your sending server matches the selector in your DKIM DNS record.

July 2024 - MailChannels
Technical article

Documentation from dmarcian shares that troubleshooting DKIM failures involves checking the DNS record for accuracy, ensuring the private key on the mail server matches the public key in DNS, and verifying that the email content hasn't been altered in transit.

July 2024 - dmarcian
Technical article

Documentation from AuthSMTP explains that DNS propagation can take time, especially after making changes. Use online tools to check if your DKIM records have propagated globally.

August 2022 - AuthSMTP