During custom email domain configuration, the email sender creation process fails with the following error message:

Not found: Resource not found: <Domain> (Domain)

• Custom Email Domain
• Domain Name System (DNS) records
• Branding
• Okta Classic Engine
• Okta Identity Engine (OIE)

During email domain configuration, the system checks for the four required Domain Name System (DNS) records: one Text (TXT) record for domain verification and three Canonical Name (CNAME) records for routing, Sender Policy Framework (SPF), and DomainKeys Identified Mail (DKIM). This check is part of the domain verification and the automatic generation of additional records. If the DNS records are not visible or unreachable, the verification fails because the system cannot validate domain ownership.

Even if the user creates the DNS records as instructed, DNS-related issues, such as slow propagation or DNS server outages, can make the records unreachable and cause this error.

To resolve this issue, follow the steps mentioned below:

1. Verify the exact spelling of the generated DNS records, ensuring no typographical errors exist in the hostname or target values.
2. Confirm that no duplicate DNS records exist for the specified domain, as conflicting records prevent successful resolution.
3. Use a public DNS lookup tool (for example, nslookup or dig) to query the TXT and CNAME records from an external network to ensure they are publicly visible.
4. Allow sufficient time for DNS propagation. Propagation can take up to 48 hours, depending on the domain's Time to Live (TTL) settings.
5. Investigate the DNS server configuration to ensure it responds to public queries and does not restrict access via firewall rules.
6. Return to the admin console and select Verify to re-initiate the domain verification process once the records are publicly resolvable.