DNS Server Not Responding: How to Fix

The "DNS server not responding" error means your device cannot reach its configured DNS resolver. Without DNS resolution, your browser cannot translate domain names into IP addresses, and no websites load. You can typically still access sites by IP address directly, but that is impractical for normal browsing.

This error differs from dns_probe_finished_nxdomain (which means the domain does not exist) in an important way: the DNS server is not responding at all, meaning the problem is between your device and the DNS resolver, not with a specific domain. Every domain will fail to resolve until the underlying connectivity issue is fixed.

Here is how to diagnose and fix the problem. For related DNS issues, see Common DNS Errors.

What Causes the Error

The error appears when your device sends a DNS query and receives no response within the timeout period. Common causes:

Your ISP's DNS servers are down. ISPs operate DNS resolvers for their customers, and these servers occasionally experience outages or degraded performance.

Your router is not forwarding DNS queries. If your router is misconfigured, overloaded, or its DNS proxy feature has crashed, DNS queries from your device never reach the upstream resolver.

Your network adapter has incorrect DNS settings. A misconfigured DNS server address (pointing to a server that does not exist or is not a DNS resolver) causes all queries to time out.

Firewall or security software is blocking DNS traffic. Firewalls can block outbound UDP port 53 (DNS) traffic, preventing queries from reaching any resolver.

Your network connection is down. If the underlying network connection (Wi-Fi, Ethernet, cellular) is not working, DNS queries cannot leave your device.

VPN or proxy interference. VPN clients often redirect DNS queries through their own resolvers. If the VPN connection is partially broken, DNS fails while other traffic may still work.

Step 1: Check if the Problem is DNS-Specific

First, determine whether the issue is DNS or a broader network problem:

# Try to ping a public IP address (no DNS needed)
ping 8.8.8.8

If the ping succeeds, your internet connection works and the problem is specifically with DNS resolution. If the ping fails, you have a broader network connectivity issue that needs to be resolved first (check your router, cables, Wi-Fi connection, or ISP status).

Step 2: Try a Different DNS Resolver

The quickest fix is to switch to a public DNS resolver. If your current DNS server is not responding, a different server may work:

Quick Test

# Test Google's DNS
nslookup google.com 8.8.8.8

# Test Cloudflare's DNS
nslookup google.com 1.1.1.1

If either of these returns a result, your internet connection is fine and the problem is with your current DNS resolver.

Changing Your DNS Settings

Windows

1. Open Settings > Network & Internet > Advanced network settings.
2. Click on your active network adapter (Wi-Fi or Ethernet).
3. Click Edit next to DNS server assignment.
4. Switch from "Automatic (DHCP)" to "Manual."
5. Enable IPv4 and enter:
   • Preferred DNS: 1.1.1.1
   • Alternate DNS: 8.8.8.8
6. Save and try browsing again.

macOS

1. Open System Settings > Network.
2. Select your active connection (Wi-Fi or Ethernet).
3. Click Details > DNS.
4. Remove existing DNS servers and add:
   • 1.1.1.1
   • 8.8.8.8
5. Click OK and Apply.

Linux

Edit your resolver configuration:

# For systems using systemd-resolved
sudo nano /etc/systemd/resolved.conf
# Add under [Resolve]:
# DNS=1.1.1.1 8.8.8.8
sudo systemctl restart systemd-resolved

# For systems using /etc/resolv.conf directly
sudo nano /etc/resolv.conf
# Replace nameserver lines with:
# nameserver 1.1.1.1
# nameserver 8.8.8.8

For a full comparison of public DNS providers, see Public DNS Providers.

Step 3: Restart Your Router

If multiple devices on your network have DNS issues, the problem is likely your router:

1. Unplug the router's power cable (and your modem if it is separate).
2. Wait 30 seconds.
3. Plug the modem back in first and wait for it to fully connect.
4. Plug the router back in and wait for it to fully boot.
5. Try browsing again.

Routers run DNS proxy services that forward queries from your devices to upstream DNS servers. These proxy services can crash or become stuck, especially on consumer-grade routers that have been running for weeks without a restart.

If the problem recurs frequently, check for router firmware updates. Outdated firmware is a common source of DNS proxy instability.

Step 4: Flush Your DNS Cache

Even after fixing the underlying issue, your device may have cached the failed DNS state:

Windows

ipconfig /flushdns

macOS

sudo dscacheutil -flushcache
sudo killall -HUP mDNSResponder

Linux

sudo systemd-resolve --flush-caches

For the complete guide, see Flush DNS Cache.

Step 5: Check Firewall and Security Software

Firewalls and security software can block DNS traffic:

Windows Firewall

1. Open Windows Security > Firewall & network protection.
2. Click Allow an app through firewall.
3. Ensure your browser is allowed through both private and public networks.

Third-Party Security Software

Temporarily disable your antivirus or internet security software and try browsing. If DNS works with the security software disabled, the software is blocking DNS queries. Check its settings for DNS filtering or web protection features and configure them to allow DNS traffic.

macOS Firewall

System Settings > Network > Firewall. If the firewall is enabled, check that it is not blocking outbound connections.

Step 6: Reset Your Network Configuration

If none of the above steps work, reset your network stack:

Windows

Open Command Prompt as Administrator:

netsh winsock reset
netsh int ip reset
ipconfig /release
ipconfig /renew
ipconfig /flushdns

Restart your computer after running these commands.

macOS

Delete network preferences and recreate them:

1. Open System Settings > Network.
2. Remove your Wi-Fi or Ethernet connection.
3. Re-add it.
4. Configure DNS settings manually.

Linux

sudo systemctl restart NetworkManager
# or
sudo systemctl restart networking

Step 7: Check for ISP DNS Outages

If the problem affects only your ISP's DNS servers and switching to a public resolver fixes it, the issue is on your ISP's end. Check:

• Your ISP's status page or social media for outage reports.
• Down detector sites for reports of DNS issues with your ISP.
• Community forums for your ISP.

ISP DNS outages are more common than most people realize. Major ISPs experience DNS degradation several times per year. Using a public DNS resolver (1.1.1.1, 8.8.8.8) as your primary DNS makes you independent of your ISP's DNS infrastructure and avoids this class of problem entirely.

Step 8: Disable IPv6 (If Necessary)

In some network configurations, IPv6 DNS resolution fails while IPv4 works. If your system is configured to prefer IPv6 and the IPv6 DNS server is not responding, the entire DNS resolution process may time out before falling back to IPv4.

Windows

1. Open Network Connections (ncpa.cpl).
2. Right-click your active adapter > Properties.
3. Uncheck "Internet Protocol Version 6 (TCP/IPv6)."
4. Click OK.

This is a diagnostic step, not a permanent solution. If disabling IPv6 fixes the issue, the real fix is to configure working IPv6 DNS servers or fix your network's IPv6 configuration.

Step 9: Run Windows Network Diagnostics

Windows has a built-in network troubleshooter that can detect and fix common DNS issues:

1. Open Settings > System > Troubleshoot > Other troubleshooters.
2. Run the "Network & Internet" troubleshooter.
3. Follow the prompts.

The troubleshooter can detect misconfigured DNS settings, adapter issues, and connectivity problems. It does not fix everything, but it is a quick automated check.

Preventing the Problem

Use a public DNS resolver as your primary DNS. This protects you from ISP DNS outages, which are the most common cause of this error.

Configure a fallback DNS server. Always set both a primary and secondary DNS server. If the primary is unreachable, your device automatically tries the secondary.

Keep your router firmware updated. Router DNS proxy bugs are a common cause of intermittent DNS failures.

Monitor your own domain's DNS. If you manage domains and want to ensure your users never see DNS errors caused by your configuration, monitor your nameservers and DNS records for availability and correctness.

References

1. Google, "Get started with Google Public DNS," https://developers.google.com/speed/public-dns/docs/using
2. Cloudflare, "Setting up 1.1.1.1," https://developers.cloudflare.com/1.1.1.1/setup/
3. Microsoft, "Fix network connection issues in Windows," https://support.microsoft.com/en-us/windows/fix-network-connection-issues-in-windows