Published 2022-02-15 by TechNet New England
When your browser shows "DNS server not responding" or "DNS_PROBE_FINISHED_NO_INTERNET," it means your computer cannot translate website names (like google.com) into IP addresses. The internet connection itself may be fine, but name resolution is broken. ## What DNS Does DNS (Domain Name System) converts human-readable website names into IP addresses that computers use to connect. When DNS fails, your browser cannot find any website, even though your internet connection may be active. ## Fix 1: Restart Your Router The simplest fix. Unplug your router for 30 seconds, plug it back in, and wait for it to fully restart. DNS issues often originate at the router level. ## Fix 2: Flush DNS Cache Your computer caches DNS lookups. A stale or corrupt cache can cause failures. **Windows:** 1. Open Command Prompt as Administrator. 2. Run: ```cmd ipconfig /flushdns ``` **Mac:** 1. Open Terminal. 2. Run: ```bash sudo dscacheutil -flushcache sudo killall -HUP mDNSResponder ``` ## Fix 3: Change DNS Servers Your ISP's DNS servers may be slow or down. Switch to a public DNS provider. **Windows:** 1. Go to Settings > Network and internet > Wi-Fi (or Ethernet) > your connection > DNS server assignment > Edit. 2. Change to Manual. 3. Enter: Preferred: `8.8.8.8` (Google) or `1.1.1.1` (Cloudflare) Alternate: `8.8.4.4` or `1.0.0.1` **Mac:** 1. Go to System Settings > Wi-Fi > Details (for your network) > DNS. 2. Remove existing entries and add: `8.8.8.8` `1.1.1.1` ## Fix 4: Disable IPv6 (Temporarily) Some DNS issues are caused by IPv6 misconfiguration. **Windows:** 1. Open Network Connections (ncpa.cpl). 2. Right-click your connection > Properties. 3. Uncheck **Internet Protocol Version 6 (TCP/IPv6)**. 4. Click OK and test. **Mac:** 1. Open System Settings > Network > Wi-Fi > Details > TCP/IP. 2. Set **Configure IPv6** to **Link-Local Only**. ## Fix 5: Reset Network Settings **Windows:** ```cmd netsh winsock reset netsh int ip reset ipconfig /release ipconfig /renew ipconfig /flushdns ``` Restart after running these commands. **Mac:** Delete network configuration files as described in our Wi-Fi troubleshooting guide, or create a new Network Location in System Settings. ## Fix 6: Try a Different Browser If one browser shows the DNS error but another works, the issue is browser-specific. Clear the failing browser's cache and DNS cache. In Chrome, go to `chrome://net-internals/#dns` and click **Clear host cache**. ## Fix 7: Check Your Firewall or Security Software Some firewalls, VPNs, or security tools can block DNS traffic. Temporarily disable them to test. If DNS works with the security software disabled, adjust its settings or contact the vendor. ## When to Contact IT If DNS issues affect all devices on your network, the problem is the router or ISP. If it only affects your device, the fixes above should resolve it. If you are on a managed network and DNS is controlled by Group Policy or a proxy, contact your IT provider.