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DNS_PROBE_FINISHED_BAD_CONFIG: How to Fix It

Chrome's diagnostic found your configured DNS server doesn't work, typically a wrong manual DNS entry, a dead VPN resolver or a broken router.

DNS_PROBE_FINISHED_BAD_CONFIG

Your internet connection works, but the DNS server your device is set to use doesn't. Chrome's check points at your DNS configuration.

Quick checks

  • Did you recently change DNS servers, install a VPN or a DNS-filtering app?
  • Restart the router.

Fixes on Mac

  1. See which DNS servers macOS uses

    1. Run scutil --dns | grep nameserver in Terminal.
    2. Test each with dig @ADDRESS example.com; one that times out is the problem.

  2. Set working DNS servers

    1. System Settings › Network › Wi-Fi › Details › DNS: remove bad entries and add 1.1.1.1 and 8.8.8.8.
    2. Flush: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder.

  3. Remove leftover DNS profiles

    1. System Settings › General › Device Management (or Profiles): remove DNS profiles you no longer use.
    2. Quit or uninstall DNS-filtering apps you've stopped using.

Fixes on Windows

  1. Reset DNS

    1. Set DNS server assignment back to Automatic (DHCP) or to public servers.
    2. Run ipconfig /flushdns.

Other devices

  1. Router

    1. Check the router's DNS settings and set public resolvers.

Still not working?

If every resolver times out from your network but works elsewhere, something on the network blocks DNS on port 53. Use encrypted DNS (DoH) in the browser, or ask the network administrator.

See what’s happening

LightAtom's connections view shows domain names reappearing on connections once lookups work again.

Frequently asked questions

What does DNS_PROBE_FINISHED_BAD_CONFIG mean?

Chrome tested DNS after a failure and found that your configured DNS servers aren't responding correctly, so the configuration is the likely cause.

How do I reset DNS on a Mac?

In System Settings › Network › Details › DNS, remove manual entries so the router's server is used, or add a public one like 1.1.1.1. Then flush the cache.

Can a VPN cause DNS_PROBE_FINISHED_BAD_CONFIG?

Yes. A VPN that disconnected uncleanly can leave its DNS servers configured. Reconnect or quit the VPN app.

Related errors and tools

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LightAtom team

The people who build LightAtom, a network monitor for macOS.