DNS_PROBE_STARTED: What It Means & How to Fix It

What Does DNS_PROBE_STARTED Mean?

DNS_PROBE_STARTED is a Chromium browser error that appears when your browser begins a DNS lookup but the query stalls before receiving any response. Chrome displays "This site can't be reached" along with the error code DNS_PROBE_STARTED — indicating the DNS resolution process initiated but never completed.

Unlike DNS_PROBE_FINISHED_NXDOMAIN (which means the DNS query completed but the domain wasn't found), DNS_PROBE_STARTED means the query never finished at all. Your browser sent a request to translate a domain name into an IP address, but the DNS resolver never responded — either because it's unreachable, frozen, or blocked.

This error affects all Chromium-based browsers: Google Chrome, Microsoft Edge, Opera, Brave, and Vivaldi. Firefox handles DNS errors differently and won't show this exact message. The error is almost always caused by a problem on your device or network — not the website you're trying to visit.

How DNS Resolution Works (And Where It Stalls)

To understand why DNS_PROBE_STARTED happens, you need to know how DNS resolution works. When you type example.com in Chrome, your browser goes through these steps to find the server's IP address:

Step 1 — Browser cache check. Chrome first checks its own internal DNS cache (chrome://net-internals/#dns) for a cached IP address. If the domain was resolved recently and the TTL (Time to Live) hasn't expired, Chrome uses the cached result instantly — no network request needed.

Step 2 — OS resolver query. If Chrome's cache misses, the request goes to your operating system's DNS resolver (the stub resolver). On Windows, this is the DNS Client service (Dnscache). On macOS, it's mDNSResponder. The OS checks its own cache before making a network call.

Step 3 — Recursive resolver query. If the OS cache also misses, the query is sent over the network to your configured DNS server (typically your ISP's resolver, or a public resolver like 8.8.8.8). This recursive resolver does the heavy lifting — querying root servers, TLD servers, and authoritative nameservers to find the answer.

Step 4 — Response returned. The recursive resolver returns the IP address to your OS, which caches it and passes it to Chrome. Chrome connects to the IP address and loads the page.

DNS_PROBE_STARTED means this process stalled at Step 2 or Step 3. The browser fired the DNS probe, but the OS resolver or network query never returned a result. This happens when the DNS Client service is frozen, your DNS server is unreachable, or a firewall is blocking port 53 (the DNS port).

What Causes DNS_PROBE_STARTED?

DNS_PROBE_STARTED is triggered when the DNS resolution process starts but can't complete. Here are the most common causes, sorted by frequency:

• DNS Client service frozen (Windows) — The Windows DNS Client service (Dnscache) handles all DNS queries for the OS. If this service freezes or crashes, every DNS probe starts but never finishes. This is the #1 cause on Windows machines.

• Corrupted DNS cache — Stale or corrupted entries in your system's DNS cache can cause lookups to fail silently. The resolver tries to use cached data, gets confused, and never sends a proper query to the network.

• DNS server unreachable — If your configured DNS server is down, overloaded, or misconfigured, DNS queries go unanswered. ISP DNS servers are notorious for intermittent outages that cause exactly this error.

• Firewall or security software blocking port 53 — DNS uses UDP port 53 (and sometimes TCP port 53). If a firewall, antivirus, or corporate proxy blocks this port, DNS queries leave your machine but never reach the resolver.

• Network adapter issues — A misconfigured, disabled, or glitching network adapter can prevent DNS packets from being sent. This is common after waking from sleep, switching between Wi-Fi and Ethernet, or after a failed driver update.

• VPN or proxy interference — VPNs redirect DNS queries through their own resolvers. If the VPN connection drops or the VPN's DNS server is unreachable, your queries go nowhere.

• Browser extensions intercepting DNS — Privacy extensions, ad blockers, and DNS-over-HTTPS extensions can intercept and modify DNS queries, sometimes breaking them entirely.

DNS_PROBE Error Codes Compared

Chrome uses several DNS_PROBE error codes, each indicating a different stage of failure in the DNS resolution process. Understanding which error you're seeing helps you diagnose the root cause faster.

The key difference: STARTED means the query is stuck in limbo — it was sent but no result came back. All FINISHED variants mean the query completed but the result was an error. STARTED is almost always a network or service problem, while FINISHED errors often point to configuration issues.

Fix 1: Flush Your DNS Cache

Corrupted or stale DNS cache entries are a leading cause of DNS_PROBE_STARTED. Flushing the cache forces your system to request fresh DNS records from the network. This fix resolves the error in about 40% of cases.

Flush DNS on Windows

Open Command Prompt as Administrator (right-click Start → Terminal (Admin)) and run these three commands in sequence:

# Flush the DNS resolver cache
ipconfig /flushdns

# Release and renew your IP address (resets DHCP)
ipconfig /release
ipconfig /renew

# Re-register DNS with your domain controller
ipconfig /registerdns

# Also flush Chrome's internal DNS cache:
# Open Chrome → navigate to chrome://net-internals/#dns → Click "Clear host cache"

Flush DNS on macOS

Open Terminal and run the appropriate command for your macOS version:

# macOS Sonoma / Sequoia / Ventura (14+)
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

# macOS Monterey / Big Sur (12-13)
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

# Verify the flush worked — should return empty:
sudo dscacheutil -cachedump

Flush DNS on Linux

The command depends on your DNS resolver. Most modern Linux distributions use systemd-resolved:

# systemd-resolved (Ubuntu 18.04+, Fedora, Arch)
sudo systemd-resolve --flush-caches

# Verify: check cache size is 0
resolvectl statistics

# If using dnsmasq (older systems)
sudo systemctl restart dnsmasq

# If using nscd
sudo systemctl restart nscd

Flush DNS on Android

Android doesn't have a terminal DNS flush command for most users. Instead:

1. Open Chrome on Android
2. Type in the address bar: chrome://net-internals/#dns
3. Tap "Clear host cache"
4. Go to chrome://net-internals/#sockets
5. Tap "Flush socket pools"
6. Restart Chrome and try loading the website again

Fix 2: Switch to a Public DNS Server

If your ISP's DNS server is slow, unreachable, or returning errors, switching to a public DNS resolver often fixes DNS_PROBE_STARTED immediately. Public resolvers like Google and Cloudflare have global anycast networks with 99.99% uptime — they almost never go down.

According to DNSPerf benchmarks, Cloudflare DNS (1.1.1.1) averages 11 ms response time globally, while ISP resolvers typically range from 30–120 ms. Faster DNS also means faster page loads.

Change DNS on Windows 10/11

# Method 1: GUI
# Settings → Network & Internet → Wi-Fi (or Ethernet) → Hardware properties
# → DNS server assignment → Edit → Manual
# → IPv4: ON → Preferred: 1.1.1.1, Alternate: 1.0.0.1 → Save

# Method 2: PowerShell (as Administrator)
# Find your adapter name first:
Get-NetAdapter | Where-Object Status -eq Up

# Set DNS (replace "Wi-Fi" with your adapter name):
Set-DnsClientServerAddress -InterfaceAlias "Wi-Fi" -ServerAddresses 1.1.1.1,1.0.0.1

Change DNS on macOS

# GUI: System Settings → Network → Wi-Fi → Details → DNS
# Remove existing entries, add: 1.1.1.1 and 1.0.0.1

# Terminal (faster):
networksetup -setdnsservers Wi-Fi 1.1.1.1 1.0.0.1

# Verify:
networksetup -getdnsservers Wi-Fi
# Expected output:
# 1.1.1.1
# 1.0.0.1

Fix 3: Restart the DNS Client Service (Windows)

The Windows DNS Client service (Dnscache) caches DNS responses and manages all DNS queries for the operating system. If this service freezes — which happens more often than you'd think — every DNS probe starts but never completes, causing DNS_PROBE_STARTED across all browsers and applications.

Restarting this service is one of the most effective fixes for this specific error on Windows. Microsoft's DNS Client handles roughly 50–200 DNS queries per minute on an average browsing session.

# Check if the DNS Client service is running:
Get-Service Dnscache | Select-Object Name, Status, StartType

# Restart the DNS Client service:
Restart-Service Dnscache -Force

# Verify it's running:
Get-Service Dnscache
# Status should be "Running"

# Alternative: Services GUI
# Press Win+R → type services.msc → Enter
# Find "DNS Client" → Right-click → Restart

Fix 4: Clear Chrome's Cache and DNS Data

Chrome maintains its own DNS cache separate from your operating system's cache. Corrupted entries in Chrome's internal cache can cause DNS_PROBE_STARTED even when your system DNS is working correctly. Clearing both caches ensures clean lookups.

Step 1: Clear Chrome's DNS cache
  → Navigate to: chrome://net-internals/#dns
  → Click "Clear host cache"

Step 2: Flush socket pools
  → Navigate to: chrome://net-internals/#sockets
  → Click "Flush socket pools"

Step 3: Clear browsing data
  → Press Ctrl+Shift+Delete (Windows/Linux) or Cmd+Shift+Delete (Mac)
  → Time range: "All time"
  → Check: ✓ Cached images and files
  → Check: ✓ Cookies and other site data
  → Click "Delete data"

Step 4: Restart Chrome completely
  → Close all Chrome windows
  → Reopen Chrome and test

Fix 5: Disable Browser Extensions

Browser extensions that modify network requests — ad blockers, privacy tools, VPN extensions, DNS-over-HTTPS add-ons — can intercept DNS queries and break the resolution process. A single misbehaving extension can cause DNS_PROBE_STARTED on every page load.

The quickest test: open an Incognito window (Ctrl+Shift+N). Incognito mode disables all extensions by default. If the website loads in Incognito, an extension is the culprit.

1. Open chrome://extensions/
2. Disable ALL extensions (toggle each one off)
3. Restart Chrome and test the website
4. If the error is gone, re-enable extensions one by one:
   → Enable one → test → if error returns, that's the culprit

Common culprits:
  • VPN browser extensions (NordVPN, ExpressVPN, Surfshark)
  • DNS-over-HTTPS extensions
  • Proxy/tunnel extensions (Hola, ZenMate)
  • Privacy extensions with custom DNS settings
  • Network debugging tools

Fix 6: Reset Network Settings

If none of the fixes above work, a full network stack reset can resolve deep-seated TCP/IP or Winsock corruption that prevents DNS communication. This resets all network adapters, DNS settings, and the TCP/IP stack to factory defaults.

Reset Network on Windows

Open Command Prompt or PowerShell as Administrator and run all four commands:

# Reset Winsock catalog (fixes corrupted network socket entries)
netsh winsock reset

# Reset TCP/IP stack to factory defaults
netsh int ip reset

# Flush DNS cache
ipconfig /flushdns

# Release and renew DHCP lease
ipconfig /release
ipconfig /renew

# IMPORTANT: Restart your computer after running these commands
# The Winsock and TCP/IP resets require a reboot to take effect

Reset Network on macOS

# Remove network preferences (forces macOS to rebuild them)
sudo rm -f /Library/Preferences/SystemConfiguration/NetworkInterfaces.plist
sudo rm -f /Library/Preferences/SystemConfiguration/preferences.plist

# Restart mDNSResponder (DNS resolver)
sudo killall -HUP mDNSResponder

# Restart the network stack
sudo ifconfig en0 down && sudo ifconfig en0 up

# Restart your Mac for a clean state

Fix 7: Check Antivirus and Firewall Settings

Antivirus programs and firewalls with "web protection" or "DNS filtering" features can intercept DNS queries on port 53 and block them if they're flagged as suspicious. Some security suites redirect all DNS traffic through their own proxy — if that proxy malfunctions, every DNS probe stalls.

To test if your security software is the problem, temporarily disable it and try loading the website. If the error disappears, add Chrome as an exception or whitelist DNS traffic (UDP port 53).

# Check if Windows Firewall is blocking DNS (port 53)
Get-NetFirewallRule | Where-Object {
  $_.Direction -eq 'Outbound' -and $_.Action -eq 'Block'
} | Get-NetFirewallPortFilter | Where-Object {
  $_.RemotePort -eq 53
}

# If a blocking rule exists, allow DNS outbound:
New-NetFirewallRule -DisplayName "Allow DNS (UDP 53)" `
  -Direction Outbound -Protocol UDP -RemotePort 53 `
  -Action Allow -Profile Any

Fix 8: Restart Your Router

Routers maintain their own DNS cache and handle DNS forwarding for all devices on your network. A router with a full DNS cache, memory leak, or frozen DNS forwarding process can cause DNS_PROBE_STARTED on every device connected to it.

A proper router restart (power cycle) clears the router's RAM, DNS cache, and re-establishes the connection to your ISP's DNS servers. This is different from a soft reboot — you need to cut the power completely.

1. Unplug the router's power cable (not just press the button)
2. Wait 30 seconds (capacitors need time to discharge fully)
3. Plug the power cable back in
4. Wait 2-3 minutes for the router to fully boot
5. Reconnect to Wi-Fi and test

If you have a separate modem:
  → Unplug the modem first, wait 30s
  → Unplug the router, wait 30s
  → Plug modem back in first, wait 2 min
  → Plug router back in, wait 2 min

How to Diagnose DNS_PROBE_STARTED

If the fixes above haven't worked, you can use diagnostic commands to pinpoint exactly where the DNS resolution chain is breaking. These commands work on all operating systems and will tell you whether the problem is your DNS server, your network, or your local configuration.

Test DNS Resolution with nslookup

# Test your current DNS server
nslookup google.com
# If this times out → your DNS server is unreachable

# Test with Google DNS directly (bypasses your configured server)
nslookup google.com 8.8.8.8
# If this works → your default DNS server is the problem

# Test with Cloudflare DNS
nslookup google.com 1.1.1.1
# If this also fails → the problem is your network, not DNS servers

Test Network Connectivity

# Test basic internet connectivity (ping by IP — no DNS needed)
ping 1.1.1.1
# If this fails → you have no internet connection at all

# Test DNS resolution (ping by hostname — requires DNS)
ping google.com
# If IP ping works but hostname ping fails → DNS is the problem

# Check if port 53 (DNS) is reachable
# Windows:
Test-NetConnection 8.8.8.8 -Port 53
# macOS/Linux:
nc -zv 8.8.8.8 53

If ping 1.1.1.1 fails but your Wi-Fi shows connected, your router may have lost its WAN connection. Check your router's admin panel (usually 192.168.1.1) for WAN status, or use DNS Robot's Ping tool from another device to verify your network.

Use Chrome's Built-In Diagnostics

Chrome has powerful internal diagnostic pages that can reveal exactly what's happening with DNS queries:

chrome://net-internals/#dns    → View cached DNS entries, clear cache
chrome://net-internals/#sockets → View active connections, flush pools
chrome://net-internals/#events  → Live event log (see DNS query lifecycle)
chrome://flags/#dns-over-https  → Check if Secure DNS is misconfigured
chrome://net-export/            → Export network log for deep analysis