You open Chrome and see "DNS_PROBE_FINISHED_BAD_CONFIG" across every website you try. Unlike a simple typo or a server that is temporarily down, this error is telling you something specific: the DNS configuration on your own computer is broken or corrupted. The good news is that it is fixable in minutes without reinstalling anything.
This guide covers 9 ranked fixes — ordered from highest to lowest success rate — for Windows, Mac, and Chrome on any platform. Follow them in order and you will almost certainly be back online before you finish reading.
Quick Answer: What Is DNS_PROBE_FINISHED_BAD_CONFIG?
DNS_PROBE_FINISHED_BAD_CONFIG means Chrome cannot connect because your DNS configuration is corrupted or misconfigured. Unlike NXDOMAIN (domain does not exist), BAD_CONFIG means your system's DNS settings themselves are broken — not just one website. Fix it by flushing the DNS cache (ipconfig /flushdns), resetting the TCP/IP stack (netsh int ip reset), switching to Google DNS (8.8.8.8), or renewing your IP address. Estimated fix time: 3 to 7 minutes.
BAD_CONFIG vs NXDOMAIN vs ERR_CONNECTION_REFUSED
Before you start fixing things, confirm you have the right error. These three Chrome errors look similar but have very different causes and solutions:
| Error | What It Means | Affects | Primary Fix |
|---|---|---|---|
| DNS_PROBE_FINISHED_BAD_CONFIG | Your system's DNS configuration is corrupted or misconfigured. Chrome cannot even properly query DNS servers. | Most or all websites | Flush DNS, reset TCP/IP, switch to Google DNS |
| DNS_PROBE_FINISHED_NXDOMAIN | The domain you typed does not exist in DNS. DNS is working fine — the address is simply not registered. | One specific URL | Check for typo, flush DNS cache, try a different DNS server |
| ERR_CONNECTION_REFUSED | DNS resolved successfully but the server at that address actively rejected the connection. The site may be down or blocking you. | One specific site | Check server status, disable firewall/VPN, clear browser cache |
If the error only affects one website, you likely have NXDOMAIN or a server issue — not BAD_CONFIG. BAD_CONFIG breaks your ability to reach most or all sites simultaneously.
Fix 1: Flush the DNS Cache (Windows)
Success rate: HIGH — resolves the issue in roughly 40% of cases. Your computer stores recent DNS lookups in a local cache. If that cache becomes stale or corrupted, Chrome cannot resolve addresses correctly.
Run ipconfig /flushdns in Command Prompt
Press Win + X and select Terminal (Admin) or search "cmd", right-click, and choose "Run as administrator." Type the following and press Enter:
ipconfig /flushdns
You should see: "Successfully flushed the DNS Resolver Cache." Now close the prompt and reload the page in Chrome. If this alone does not fix it, continue to Fix 2 before restarting.
Fix 2: Reset the TCP/IP Stack
Success rate: HIGH — particularly effective when the error appeared after a software install or Windows update. The TCP/IP stack and Winsock catalog can become corrupted, causing all DNS resolution to fail even when individual settings look correct.
Run both reset commands in Admin Command Prompt
In the same admin Command Prompt from Fix 1, run these two commands one at a time, pressing Enter after each:
netsh int ip reset
netsh winsock reset
Both commands will report the changes they made (you may see several lines of output). Restart your computer after running both commands — these resets do not take effect until after a full reboot. After restarting, test Chrome before moving on.
Run Fixes 1 and 2 together before rebooting
Since both Fix 1 and Fix 2 require an admin Command Prompt, run all three commands (ipconfig /flushdns, netsh int ip reset, netsh winsock reset) in one session, then reboot once. This saves time and means the single restart handles all three changes simultaneously.
Fix 3: Switch to Google DNS (8.8.8.8 / 8.8.4.4)
Success rate: HIGH. Your ISP's default DNS servers are often slow, unreliable, or temporarily broken. Switching to Google's public DNS servers (8.8.8.8 and 8.8.4.4) bypasses your ISP's servers entirely and typically resolves BAD_CONFIG errors caused by a bad DNS server assignment.
On Windows
Change DNS via Network Adapter Properties
Press Win + R, type ncpa.cpl, press Enter. Right-click your active network adapter (Wi-Fi or Ethernet) and select Properties. Double-click Internet Protocol Version 4 (TCP/IPv4). Select "Use the following DNS server addresses" and enter:
Preferred DNS server: 8.8.8.8
Alternate DNS server: 8.8.4.4
Click OK on both dialogs. Open a new tab in Chrome and test. No restart required for this change.
On Mac
Change DNS in System Settings
Open System Settings (macOS Ventura and later) or System Preferences (macOS Monterey and earlier) > Network. Select your active connection (Wi-Fi or Ethernet) and click Details (or Advanced on older macOS). Go to the DNS tab. Click the + button and add 8.8.8.8, then add 8.8.4.4. Remove any existing DNS entries that look suspicious or are your ISP's addresses. Click OK > Apply. Flush the Mac DNS cache by opening Terminal and running:
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
Fix 4: Release and Renew Your IP Address
Success rate: HIGH. If your router's DHCP server sent your computer a bad DNS configuration, releasing and renewing your IP forces a fresh assignment — including fresh, valid DNS server addresses from the router.
ipconfig /release then ipconfig /renew
In an admin Command Prompt, run these two commands in order:
ipconfig /release
ipconfig /renew
The /release command drops your current IP and DNS configuration. The /renew command requests a fresh one from your router. You will briefly lose network connectivity between the two commands — this is normal. After /renew completes, your new IP and DNS addresses will be shown. Test Chrome immediately — no restart needed.
Fix 5: Restart Your Router and Modem
Success rate: MEDIUM. A router that has been running for days or weeks can develop memory issues that cause it to serve corrupt DHCP/DNS data to connected devices. A cold restart clears this.
Full power cycle — not just a restart button press
Unplug the power cable from your modem and router (if they are separate devices, unplug both). Wait 30 full seconds. Plug the modem back in first — wait until its lights stabilize (usually 1–2 minutes). Then plug the router in and wait another minute. Reconnect your computer to Wi-Fi or Ethernet. Run ipconfig /flushdns after reconnecting to clear any stale cache entries, then test Chrome.
Fix 6: Disable IPv6 Temporarily
Success rate: MEDIUM. Conflicts between IPv4 and IPv6 DNS resolution are a documented cause of BAD_CONFIG errors, especially after VPN software installs or network driver updates. Disabling IPv6 forces Chrome to use only IPv4 DNS, which often resolves the conflict.
Uncheck IPv6 in Network Adapter Properties
Press Win + R, type ncpa.cpl, press Enter. Right-click your active adapter > Properties. In the list of items, find Internet Protocol Version 6 (TCP/IPv6) and uncheck its checkbox. Click OK. Test Chrome. If this fixes the error, you can re-enable IPv6 later and investigate what is causing the conflict (often a VPN client or an outdated network adapter driver). On Mac, IPv6 is disabled per-interface under System Settings > Network > Details > TCP/IP > Configure IPv6 > set to "Link-local only."
Fix 7: Clear Chrome's Internal DNS Cache
Success rate: MEDIUM. Chrome maintains its own separate DNS cache on top of Windows's system cache. If Chrome's internal cache is corrupted, flushing the system DNS (Fix 1) will not clear it.
Use chrome://net-internals/#dns
In Chrome's address bar, type exactly: chrome://net-internals/#dns and press Enter. Click the Clear host cache button. Then navigate to chrome://net-internals/#sockets and click Flush socket pools. This clears Chrome's internal DNS and socket state completely. No restart needed — open a new tab and test immediately. If this resolves it but other browsers still fail, the problem was Chrome-specific caching; if other browsers also fail, the system-level fixes (1–4) are the right path.
Fix 8: Run the Windows Network Troubleshooter
Success rate: LOW to MEDIUM. The built-in troubleshooter catches a subset of DNS errors automatically but misses many BAD_CONFIG causes. Still worth running if you prefer not to use the command line, or if you want Windows to document what it finds.
Settings > System > Troubleshoot
On Windows 11: Settings > System > Troubleshoot > Other troubleshooters. Click Run next to "Internet Connections." On Windows 10: Settings > Update & Security > Troubleshoot > Additional troubleshooters > Internet Connections > Run the troubleshooter. Follow the prompts. If it identifies a problem and applies a fix, restart and test. Even if it says "No issues found," the underlying problem can still exist — the troubleshooter simply did not detect it.
Fix 9: Reinstall the Network Adapter Driver
Success rate: LOW (but resolves persistent cases after all else fails). A corrupted network adapter driver can cause the operating system to report bad DNS configuration data to applications like Chrome, even when the DNS settings themselves are correct.
Uninstall then reinstall clean from the manufacturer
Press Win + X > Device Manager. Expand Network Adapters. Right-click your network adapter > Uninstall device. Check "Delete the driver software for this device." Click Uninstall. Download the latest driver from your computer manufacturer's support page (dell.com/support, support.hp.com, support.lenovo.com, asus.com/support) using your laptop's model number. Install it and restart. This gives the adapter a completely clean driver state — no corrupted files carried over from the previous installation.
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Why DNS_PROBE_FINISHED_BAD_CONFIG Happens
Understanding the root cause helps you choose the right fix faster. The five most common triggers are:
- Corrupted local DNS cache — The most common cause. Your resolver cache accumulates bad entries over time, especially after network interruptions or rapid switching between networks (office Wi-Fi to home to mobile hotspot). Fix: ipconfig /flushdns.
- VPN or antivirus modifying DNS settings — VPN clients and security software frequently override your DNS server addresses. If they crash or are uninstalled improperly, they can leave invalid DNS settings behind. Fix: switch to Google DNS manually, or reinstall the VPN client cleanly.
- Windows update corrupting the network stack — Certain cumulative updates have introduced bugs in the TCP/IP stack or Winsock catalog. Fix: netsh int ip reset + netsh winsock reset, then restart.
- ISP DNS server outage — Your ISP's DNS servers occasionally go offline or return incorrect data. Fix: switch to Google DNS (8.8.8.8) or Cloudflare DNS (1.1.1.1) to bypass your ISP's servers entirely.
- Manually entered incorrect DNS addresses — If someone previously changed the DNS settings on your adapter to a server that no longer exists or is unreachable, every DNS query fails. Fix: switch to Google DNS or set back to "Obtain DNS server address automatically."
BAD_CONFIG on Mac: Complete Fix Sequence
Mac users see this error less often than Windows users, but it occurs. The fix sequence is:
- Open System Settings > Network, select your connection, click Details, go to DNS, and replace existing DNS entries with
8.8.8.8and8.8.4.4. Click OK > Apply. - Open Terminal (Applications > Utilities > Terminal) and run:
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
Enter your Mac password when prompted. - Go to System Settings > Network > your connection > Details > TCP/IP and click Renew DHCP Lease.
- Restart Chrome. If the error persists, restart the Mac.
These four steps resolve BAD_CONFIG on Mac in the overwhelming majority of cases. If they do not, the issue is likely a corrupted network profile — delete the current network location (System Settings > Network > Location > Edit Locations, delete the current one and create a new one called "Home" or "Work") and reconfigure from scratch.
Frequently Asked Questions
What is the difference between DNS_PROBE_FINISHED_BAD_CONFIG and DNS_PROBE_FINISHED_NXDOMAIN?
NXDOMAIN (Non-Existent Domain) means the domain you typed does not exist in DNS — the DNS system is working, there is simply no record for that address. BAD_CONFIG is more serious: your computer's own DNS configuration is corrupted, so Chrome cannot properly query any DNS server. NXDOMAIN affects only one site; BAD_CONFIG typically affects all or most sites at the same time.
Can DNS_PROBE_FINISHED_BAD_CONFIG affect all browsers, not just Chrome?
Yes. Because BAD_CONFIG is a system-level DNS problem, the same broken settings affect Firefox, Edge, Safari, and any other browser. Chrome surfaces it as DNS_PROBE_FINISHED_BAD_CONFIG; Firefox shows "Unable to connect"; Edge shows "Hmmm, can't reach this page." Fixing the system DNS resolves it across all browsers simultaneously.
Does restarting the router fix DNS_PROBE_FINISHED_BAD_CONFIG?
Sometimes. If the router's DHCP server pushed corrupted DNS data to your computer, restarting the router clears its memory. Combine the router restart with ipconfig /release and ipconfig /renew on Windows so your computer requests a fresh DNS configuration from the newly restarted router. If the problem is in your computer's local DNS cache or TCP/IP stack rather than the router, a router restart alone will not fix it.
Is DNS_PROBE_FINISHED_BAD_CONFIG caused by a virus?
Rarely, but it is possible. Some malware deliberately alters DNS settings to redirect traffic through malicious servers, which can produce BAD_CONFIG errors if the redirect breaks. More commonly the cause is a corrupted DNS cache, a Windows update, a VPN program, or incorrectly entered DNS server addresses. If you cannot identify a clear non-malware cause after following this guide, run a malware scan with Windows Defender or Malwarebytes.
How do I fix DNS_PROBE_FINISHED_BAD_CONFIG on a Mac?
On Mac: (1) Go to System Settings > Network > your connection > Details > DNS tab, replace existing entries with 8.8.8.8 and 8.8.4.4, click OK > Apply. (2) Open Terminal and run: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder. (3) Go to TCP/IP tab and click Renew DHCP Lease. (4) Restart Chrome. These steps resolve the error on Mac in most cases without needing a full system restart.
Comments (4)
Fixes 1 and 2 together did it for me. Ran all three commands — flushdns, netsh int ip reset, netsh winsock reset — in one Command Prompt session, rebooted, and Chrome came back immediately. I had been getting BAD_CONFIG on every single site for two days. Very clear instructions, the exact commands made it easy to follow without second-guessing anything.
Fix 3 was the one that worked for me. My ISP's DNS servers had been having problems for a few hours. Switched to 8.8.8.8 and 8.8.4.4 in the adapter properties and it was fixed instantly — no restart needed. Switching back to automatic a few hours later once my ISP sorted themselves out worked fine too.
Mine was Fix 6 — the IPv6 conflict. I had installed a VPN the day before and it had clearly messed with my IPv6 settings without cleaning up after itself. Unchecked IPv6 in adapter properties and Chrome worked right away. The comparison table between BAD_CONFIG, NXDOMAIN, and ERR_CONNECTION_REFUSED at the top was genuinely helpful — I had been misdiagnosing it as a server problem for a while.
On a Mac here. The Mac section was exactly what I needed — especially the Terminal command for flushing the DNS cache. Between changing to 8.8.8.8 and running dscacheutil, the error was gone in under two minutes. Renew DHCP Lease step was new to me but made sense. Bookmarked this for next time.
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