Nameserver error

Updated 9 October 2026

Short answer

Your domain's nameservers are the servers that answer "where is this domain?". They're set at your registrar (where you bought the domain). A nameserver error means those servers aren't giving a proper answer: they're wrong (pointing at an old DNS provider), the DNS provider doesn't have your domain set up, or one of them is down. Compare the nameservers set at your registrar with the ones your DNS provider tells you to use.

What's the problem

DNS checkers report "lame delegation", SERVFAIL, nameservers not responding, or a nameserver mismatch. Your site doesn't load, or loads only some of the time.

Why it happens

  • Nameservers set at the registrar don't match your DNS provider, for example still pointing at an old host after moving.
  • The DNS provider doesn't have the zone, for example it was deleted or never added.
  • A typo in a nameserver name.
  • Mixed nameservers from two providers, so answers differ.
  • DNSSEC records left at the registrar for an old provider.

How to fix it

  1. Find which provider you mean to use for DNS, and the exact nameservers it gives you.
  2. Check what's set at the registrar, and replace them so they match exactly. Don't mix providers.
  3. Make sure the provider has your domain and all its records.
  4. Remove or update DNSSEC at the registrar if you changed providers.
  5. Allow up to 24 hours for the change to take effect.

What Preventionlabs checks

One click runs the full report on your domain. For this problem it shows your DNS: nameservers, addresses, DNSSEC, and records pointing at services that no longer exist; your domain's registration and expiry date; whether your site loads, how fast, and where its redirects go. With Cloudflare connected, it also shows DNS changes in the last 7 days.

Run your free report

Your first report is free, no card needed. Then A$50 a month, up to 10 domains. Read-only: it never changes anything.

Sources

  1. Cloudflare: Change your nameservers (Full setup)official docsWait up to 24 hours while your registrar updates your nameservers.
  2. MDN Web Docs: DNSglossaryDNS (Domain Name System) is a hierarchical and decentralized naming system for Internet-connected resources.

Related

Domain not working Check three things in order: the domain hasn't expired, its nameservers are the ones you expect, and its DNS records point at your current host. DNS error A DNS error means the name couldn't be turned into an address. Check whether it fails everywhere or only on your network, then check the domain's records. DNS propagation: how long it takes A record change reaches everyone within its TTL, often minutes to hours. A nameserver change can take up to 24 hours. Here's how to check and speed it up. DNS not resolving: NXDOMAIN NXDOMAIN means DNS says the name doesn't exist at all. Usually a typo, an expired domain, a missing record for that subdomain, or broken nameservers.
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