Can A Domain Have Two Mail._domainkey

Can a Domain Have Two mail._domainkey Records? The Definitive Answer

The short answer is: No, a domain should not have two mail._domainkey records. While technically a DNS server might allow it, having multiple records will cause significant problems with email authentication and deliverability. This article will explain why, and what to do if you encounter this situation.

This meta description explains the core issue: having multiple mail._domainkey records creates email authentication problems and poor deliverability. It's crucial to have only one correctly configured record.

Understanding DKIM and mail._domainkey

DomainKeys Identified Mail (DKIM) is an email authentication method that uses public-private key pairs to verify that an email message truly originated from the claimed domain. The mail._domainkey record in your DNS zone file holds the public key that receiving mail servers use to verify the signature in the email header. This signature proves that the email wasn't forged or tampered with during transit. Think of it as a digital signature for your emails.

Why Only One mail._domainkey Record is Allowed

Email servers check the mail._domainkey record to validate the DKIM signature. If they find multiple records, they're presented with conflicting information, leading to authentication failure. This means your emails are more likely to be flagged as spam or rejected outright by email providers like Gmail, Outlook, and Yahoo. The receiving server has no reliable way to determine which key is the legitimate one, rendering both useless.

• Inconsistency and Confusion: Multiple records create a conflict. The email server can't determine which key is valid, leading to authentication failures.
• Increased Spam Filtering: Email providers heavily rely on DKIM for spam detection. A misconfigured DKIM setup, including multiple mail._domainkey records, significantly increases the chances of your emails ending up in spam folders.
• Delivery Issues: Failed DKIM authentication directly impacts email deliverability. Your emails are less likely to reach the recipient's inbox.

Troubleshooting Multiple mail._domainkey Records

If you've discovered multiple mail._domainkey records associated with your domain, you need to immediately investigate and rectify the situation. The most common causes are:

• Multiple email platforms: Perhaps you're using more than one email marketing service or email sending platform, each trying to set up its own DKIM. You should consolidate your email sending through a single platform.
• Manual errors: A mistake in DNS management could lead to accidentally adding duplicate records. Careful review and deletion of unnecessary records is crucial.
• Outdated configuration: An old, unused DKIM record might still be present. This needs to be removed.
• Third-party applications: Some applications or plugins automatically configure DKIM. Make sure you're aware of all such applications and their DKIM settings.

Actionable Steps:

1. Identify the source: Determine which service or application created the extra mail._domainkey records.
2. Remove the unnecessary records: Carefully delete the incorrect or obsolete records from your DNS settings. Only keep one, correctly configured mail._domainkey record associated with your primary email sending method.
3. Verify the remaining record: Use a DKIM checker tool (many are available online) to confirm that the remaining mail._domainkey record is valid and correctly configured.
4. Monitor email deliverability: After making changes, monitor your email deliverability rates closely to ensure that the issue is resolved.

By ensuring that you only have one valid mail._domainkey record, you'll significantly improve your email authentication and ensure your messages reach their intended recipients. Remember, proper email authentication is crucial for maintaining a good sender reputation and maximizing your email marketing effectiveness.