How to Change DKIM Selector
This article explains what a DKIM selector is, when you might need to change it, and how to switch selectors in MailerLogic without disrupting email authentication.
Who can use this guide: Account owners, admins, and team members with the Manage Emails role.
What Is a DKIM Selector?
When MailerLogic sends an email, it signs the message with a DKIM key. Receiving mail servers verify the signature by looking up the public key in your domain's DNS records.
The DNS record name follows this format:
<selector>._domainkey.<your-domain>
The selector is the first part of the record name. MailerLogic uses mail by default. For example, the DKIM record for example.com would be:
mail._domainkey.example.com
Each email identifies the selector used to sign it, allowing receiving servers to find the corresponding public key. A domain can have multiple DKIM records under different selectors.
When Should You Change Your DKIM Selector?
Change your selector if another email provider already uses it mail._domainkey for your domain. This can happen when you use Google Workspace, Microsoft 365, or another email marketing platform alongside MailerLogic.
Two providers should not overwrite the same DKIM record. Replacing another provider's key with MailerLogic's key can cause that provider's emails to fail DKIM verification. Keeping the other provider's key in place can prevent MailerLogic's emails from passing DKIM verification.
Using a separate selector allows both providers to maintain their own DKIM records.
You don't need to change your selector if:
The
mail._domainkeyrecord is unused or already contains MailerLogic's DKIM key.You only want to generate a fresh DKIM key. Changing the selector does not generate a new key pair.
Before You Begin
Before changing your selector, keep the following in mind:
Your key pair remains unchanged. Changing the selector moves the same public key to a different DNS record name.
Choose a selector. You can use
mail(the default),mailerlogic, or a custom selector.Follow the custom selector rules. Custom selectors must contain 1–63 characters, using lowercase letters, digits, and hyphens. They cannot start or end with a hyphen. Uppercase letters are converted to lowercase.
Prepare DNS access. You may need to add a TXT record through your DNS provider, such as Cloudflare, GoDaddy, or Amazon Route 53.
How to Change Your DKIM Selector
Step 1: Open the Domain's DNS Records
Go to 'Domains' → 'Sending Domains', find your domain, and open its 'DNS Records'.
Step 2: Choose a New Selector
At the top of the 'DNS Records' window, find the 'DKIM selector'.
Choose 'Mailerlogic' or 'Custom selector' from the dropdown. If you select 'Custom selector', enter your preferred selector in the field that appears.
Step 3: Publish the New DNS Record
If your domain is already verified, publish the new DKIM record before clicking 'Change selector'. This helps ensure that receiving servers can find the new record when MailerLogic starts signing emails with the new selector.
At your DNS provider, add a TXT record using the following details:
| Field | Value |
|---|---|
| Name / Host | <new-selector>._domainkey (some providers require the full name, such as mailerlogic._domainkey.example.com) |
| Value | The same DKIM public key value shown in your current MailerLogic DKIM record |
If your domain is not yet verified, you can change the selector first and then publish the record displayed in the DNS view.
Step 4: Change the Selector and Confirm
Click 'Change selector'.
Review the confirmation dialog, which displays the new record name and reminds you to keep the old record. Confirm the change to proceed.
After the change succeeds, MailerLogic displays a confirmation message:
"Selector saved: <selector>. The key pair is unchanged."
The DNS view refreshes to display the DKIM record under its new name.
Keep the Old DNS Record
Keep the old DKIM record in place for a few days after switching. Emails sent before the change may still be in transit and may have been signed using the old selector.
Verify the Domain if Needed
Use 'Verify' on the domain to confirm that MailerLogic can detect the DKIM record under the new selector.
If verification fails, check that the new TXT record has been added correctly and that DNS propagation is complete.
Troubleshooting
| Message | What It Means | What to Do |
|---|---|---|
| Use 1–63 letters, digits, or hyphens. Do not start or end with a hyphen. | The custom selector does not meet the naming requirements. | Use a valid selector and remove unsupported characters. |
Publish the current DKIM public key at <record name>… | The domain is verified, but the new DNS record is not yet visible. | Publish the TXT record, allow time for propagation, and try again. |
| Selector changed, but DNS refresh failed. Reload the DNS view. | The selector change succeeded, but the page could not refresh the DNS information. | Close and reopen DNS Records. |
| Domain not found or this server does not support selector changes… | The domain may no longer be available in the current list, or selector changes may not be supported for the account. | Refresh the page. If the problem persists, contact support. |
| Your API key lacks domain management permission… | The API key does not have the required permissions to manage domains. | Ask the account owner to review the API key permissions or contact support. |
Frequently Asked Questions
Does changing the selector generate a new DKIM key?
No. The key pair remains unchanged. Only the DNS record name changes.
Can I switch back to mail later?
Yes. Follow the same steps and choose mail (default). For a verified domain, ensure that mail._domainkey contains MailerLogic's public key before switching back.
Will changing the selector affect email deliverability?
It should not disrupt DKIM authentication if the new record is published before switching and the old record is retained for a few days. If receiving servers cannot find the selector used to sign an email, DKIM verification may fail.
Who can change the selector?
Account owners, admins, and team members with the Manage Emails role can change the selector. View-only and Manage CRM members can view DNS records but cannot change the selector.
Do I need to change SPF or DMARC?
No. Changing the DKIM selector does not require changes to your SPF or DMARC records.
