Fix: DNS_PROBE_FINISHED_NXDOMAIN error

The ‘DNS_PROBE_FINISHED_NXDOMAIN’ error occurs when your browser cannot resolve a domain name to an IP address, indicating that the domain doesn’t exist or there’s a DNS resolution problem.

---

How the Error Happens

This error typically occurs when:

• Domain name doesn’t exist or is misspelled
• DNS server is unreachable or misconfigured
• Domain registration has expired
• DNS propagation delays
• Local DNS cache issues
• Firewall or security software blocking DNS
• ISP DNS server problems

---

Solution 1: Verify Domain Name Spelling

# ✅ Check if domain exists
nslookup example.com

# ✅ Verify domain spelling
# Wrong: exmaple.com (missing 'a')
# Correct: example.com

# ✅ Use dig to check DNS records
dig example.com

# ✅ Check whois information
whois example.com

# ✅ Test domain with ping
ping example.com

# ✅ Test with different tools
curl -I http://example.com

---

Solution 2: Flush DNS Cache

REM ✅ On Windows
ipconfig /flushdns

REM ✅ Reset Winsock
netsh winsock reset

REM ✅ Reset IP stack
netsh int ip reset

REM ✅ Restart DNS client service
net stop dnscache
net start dnscache

# ✅ On macOS
sudo dscacheutil -flushcache
sudo killall -HUP mDNSResponder

# ✅ Alternative on macOS
sudo discoveryutil udnsflushcaches

# ✅ On Linux
sudo systemctl restart systemd-resolved
# OR
sudo service networking restart
# OR
sudo /etc/init.d/networking restart

# ✅ Clear DNS cache
sudo resolvectl flush-caches
# OR on older systems
sudo /etc/init.d/dns-clean start

---

Solution 3: Change DNS Servers

REM ✅ On Windows - Use Google DNS
REM 1. Open Network Connections
REM 2. Right-click your network adapter
REM 3. Go to Properties
REM 4. Select Internet Protocol Version 4 (TCP/IPv4)
REM 5. Click Properties
REM 6. Select "Use the following DNS server addresses"
REM 7. Enter:
REM    Preferred DNS server: 8.8.8.8
REM    Alternate DNS server: 8.8.4.4

# ✅ On Linux - Edit /etc/resolv.conf
sudo nano /etc/resolv.conf

# ✅ Add these lines:
nameserver 8.8.8.8
nameserver 8.8.4.4
# OR Cloudflare DNS:
nameserver 1.1.1.1
nameserver 1.0.0.1

# ✅ On macOS - Use networksetup
sudo networksetup -setdnsservers Wi-Fi 8.8.8.8 8.8.4.4
# OR for Ethernet:
sudo networksetup -setdnsservers Ethernet 8.8.8.8 8.8.4.4

---

Solution 4: Check Domain Availability

# ✅ Check if domain is registered
whois example.com

# ✅ Check domain status
nslookup -type=soa example.com

# ✅ Verify DNS records exist
dig example.com A
dig example.com MX
dig example.com NS

# ✅ Check domain with different DNS servers
nslookup example.com 8.8.8.8
nslookup example.com 1.1.1.1

---

Solution 5: Restart Network Services

REM ✅ On Windows - Restart network adapter
netsh interface set interface "Wi-Fi" admin=disable
netsh interface set interface "Wi-Fi" admin=enable

REM ✅ Or restart network adapter via PowerShell
PowerShell -Command "Disable-NetAdapter -Name 'Wi-Fi' -Confirm:$false; Enable-NetAdapter -Name 'Wi-Fi' -Confirm:$false"

# ✅ On Linux - Restart network
sudo systemctl restart NetworkManager
# OR
sudo systemctl restart networking

# ✅ Bring interface down and up
sudo ip link set eth0 down
sudo ip link set eth0 up

# ✅ On macOS - Renew DHCP lease
sudo ipconfig set Wi-Fi DHCP
# OR
sudo killall -HUP mDNSResponder

---

Solution 6: Check Hosts File

REM ✅ On Windows - Check hosts file
notepad C:\Windows\System32\drivers\etc\hosts

REM ✅ Look for any entries that might block the domain
REM Comment out or remove incorrect entries like:
REM 127.0.0.1 example.com

# ✅ On macOS/Linux - Check hosts file
sudo nano /etc/hosts

# ✅ Look for entries that might block the domain
# Remove or comment out incorrect entries

---

Solution 7: Disable VPN or Proxy

# ✅ If using VPN, disconnect and test
# 1. Disconnect from VPN
# 2. Try accessing the website again
# 3. If it works, the VPN DNS might be misconfigured

# ✅ Check proxy settings
# In browser:
# Chrome: Settings > Advanced > System > Open proxy settings
# Firefox: Preferences > General > Network Settings

# ✅ Or check system proxy
# Windows: netsh winhttp show proxy
# Remove proxy if not needed:
# netsh winhttp reset proxy

---

Solution 8: Use Browser-Specific Solutions

// ✅ Clear browser DNS cache
// In Chrome: chrome://net-internals/#dns
// Click "Clear host cache"

// ✅ In Firefox: about:config
// Search for "network.dnsCacheExpiration" and reset

# ✅ Try incognito/private browsing mode
# This bypasses browser DNS cache

# ✅ Try different browser
# To determine if it's browser-specific

---

Solution 9: Check Firewall and Security Software

REM ✅ Temporarily disable Windows Firewall
REM 1. Open Windows Security
REM 2. Go to Firewall & network protection
REM 3. Turn off firewall temporarily for testing
REM 4. Re-enable after testing

# ✅ Check if security software is blocking DNS
# Temporarily disable antivirus DNS protection
# Check if ad blockers are interfering

---

Solution 10: Advanced DNS Troubleshooting

# ✅ Check DNS resolution path
tracert example.com
# OR on Linux/macOS
traceroute example.com

# ✅ Check current DNS servers
# Windows
ipconfig /all | findstr "DNS"
# Linux
cat /etc/resolv.conf
# macOS
scutil --dns | grep nameserver

# ✅ Test DNS resolution with different tools
nslookup example.com
dig example.com
host example.com

# ✅ Check for DNS leaks
curl ifconfig.me

---

Prevention Tips

1. Verify domain spelling: Always double-check domain names
2. Use reliable DNS: Stick to trusted DNS providers like Google or Cloudflare
3. Keep systems updated: Ensure OS and network drivers are current
4. Monitor domain status: Regularly check domain registration status
5. Flush DNS regularly: Periodically clear DNS cache
6. Check security software: Ensure security tools don’t block legitimate DNS
7. Use multiple DNS: Configure backup DNS servers
8. Monitor network: Keep an eye on network connectivity

---

When to Contact Support

Contact your ISP, domain registrar, or network administrator when:

• Following all troubleshooting steps still results in DNS errors
• Suspected ISP DNS server issues
• Need to investigate domain registration problems
• Encountering network infrastructure issues
• Experiencing widespread DNS resolution problems