Internet & modems

DNS server not responding error

A 'DNS server not responding' message means your device can't translate website names into addresses even though the underlying connection may be fine, and switching to a public DNS server or restarting equipment usually fixes it.

Difficulty
Moderate
Time
10–20 minutes
DIY cost
$0
Pro cost
$0–$80

Symptoms

  • Browser shows 'DNS server not responding' or 'this site can't be reached'
  • Some sites load by typing their IP address but not by name
  • Problem affects all browsers on the device, not just one
  • Other devices on the same network have the same issue

Likely causes

  • CommonRouter or ISP's DNS server having a temporary problemDNS servers occasionally have outages or slow responses independent of your actual internet connection.
  • CommonRouter or modem needs a restartA stuck DNS relay in the router can cause this even when the internet itself is working.
  • PossibleDevice's own DNS cache is outdated or corruptedDevices store recently looked-up addresses, and a corrupted cache can cause lookup failures.
  • PossibleSecurity software or VPN interfering with DNS requestsSome antivirus or VPN tools intercept DNS traffic and can occasionally cause failures.

What to do

  1. Restart the router and modem, since this often resolves temporary DNS relay issues.
  2. Try loading a website by its IP address (search for its IP if unsure); if that works but the name doesn't, DNS is confirmed as the specific problem.
  3. On Windows, open Command Prompt and run 'ipconfig /flushdns' to clear the local DNS cache; on Mac, run 'sudo dscacheutil -flushcache' in Terminal.
  4. Change your device or router's DNS settings to a public DNS provider like 8.8.8.8 and 8.8.4.4 (Google) or 1.1.1.1 (Cloudflare) instead of the automatic ISP-provided one.
  5. Temporarily disable any VPN or third-party security software to see if it's interfering with DNS lookups.
  6. Restart the affected device fully, not just the browser.
  7. If the problem affects only one device even after these steps, check that device's network adapter settings for a manually entered incorrect DNS address.

Tools and parts

  • Computer for command line access

When to call a pro

Not usually needed for this issue; switching to a public DNS provider resolves the vast majority of these errors.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.