Err Name Resolution Failed? Fix DNS Errors

“Err name resolution failed” means your browser or app could not translate a website’s domain name (like example.com) into an IP address, so the connection was blocked before it even started. This guide explains the common causes and gives you step-by-step fixes for Windows, macOS, Android, iOS, and router issues, so you can get back online quickly.

What Does “Name Resolution” Actually Mean?

Every device on the internet is reached by a numeric IP address, such as 142.250.190.46 for a Google server. Humans remember names, not numbers, so the Domain Name System (DNS) acts as the internet’s phonebook. When you type a URL, your device sends a query to a DNS server asking, “What is the IP address for this name?” If that query fails—because the server is unreachable, the answer is refused, or the name doesn’t exist—you get an error like “ERR_NAME_RESOLUTION_FAILED” (Chrome), “Server not found” (Firefox), or “Cannot resolve host” (curl).

Why Does This Error Happen? (Common Causes)

DNS server outage or misconfiguration: Your ISP’s DNS server may be down, or your router is pointing to a server that no longer works.
Incorrect DNS settings on your device: A leftover static IP or manual DNS entry from a previous network can break resolution.
Cache corruption: Your OS or browser may have stored a bad DNS result that it keeps reusing.
Router issues: The router’s DNS relay can fail, especially after a power outage or firmware update.
Firewall or antivirus blocking: Security software sometimes intercepts DNS queries and blocks them.
Typo or nonexistent domain: If the name is genuinely misspelled or the site is down, no fix on your side will help.

How to Fix It on Windows

Flush the DNS cache: Open Command Prompt as Administrator and run ipconfig /flushdns. This clears stored results.
Release and renew your IP: Run ipconfig /release then ipconfig /renew. This forces a fresh DHCP lease, which often updates DNS settings.
Change DNS servers: Go to Settings > Network & Internet > Wi-Fi (or Ethernet) > Hardware properties > Edit DNS assignment. Switch from Automatic to Manual and enter 1.1.1.1 (Cloudflare) and 8.8.8.8 (Google) as preferred and alternate DNS.
Restart the DNS Client service: In Services (Win+R, type services.msc), find “DNS Client,” right-click and select Restart.
If all else fails, restart your router and then your PC. A simple reboot clears many transient network faults.

How to Fix It on macOS and Mobile

macOS: Go to System Settings > Network > your active connection > Details > DNS. Click the + sign and add 1.1.1.1 and 8.8.8.8. Then flush the cache by opening Terminal and running sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder.

Android: Open Settings > Wi-Fi, tap your network, and modify it. Change IP settings to Static (or DHCP with custom DNS) and enter 1.1.1.1 and 8.8.8.8 in the DNS fields. Alternatively, install a private DNS provider (some are built into newer Android versions under Settings > Network > Private DNS).

iOS: Go to Settings > Wi-Fi, tap the “i” next to your network, scroll to Configure DNS, select Manual, and add 1.1.1.1 and 8.8.8.8. Delete any existing entries first.

Router-Level Fixes and When to Do Them

If every device on your network shows the same error, the problem is almost certainly at the router or ISP level. First, power-cycle the router: unplug it for 30 seconds, plug it back in, and wait for the lights to stabilize. Then log into the router’s admin page (usually 192.168.1.1 or 192.168.0.1) and look for DNS settings under WAN or Internet. Change them from “Get automatically from ISP” to manual, entering 1.1.1.1 and 8.8.8.8. Save and reboot. If the error persists, contact your ISP—there may be an outage in your area.

What If Changing DNS Doesn’t Work?

If the error only appears on one site, check if the site is actually down using a service like DownForEveryoneOrJustMe (but note, that site itself needs DNS to load). If the site is up, try clearing your browser’s cache and cookies, or use a different browser. If the error appears on all sites, try disabling your firewall and antivirus temporarily to see if they are blocking DNS queries. If that fixes it, add an exception for your browser or the DNS service. Another possibility is a corrupted hosts file on Windows—open it in Notepad as Administrator (C:\Windows\System32\drivers\etc\hosts) and remove any lines with the affected domain that aren’t commented out with #.

Frequently Asked Questions

Q: Is “ERR_NAME_RESOLUTION_FAILED” the same as “DNS_PROBE_FINISHED_NXDOMAIN”?
No. NXDOMAIN means the DNS server answered but said the name doesn’t exist (a typo or deleted domain). The resolution failed error means the query never got a valid answer—the server was unreachable, timed out, or refused.

Q: Can I fix this by restarting my computer?
Often yes, because a restart clears the DNS cache and re-establishes network connections. It’s the first thing to try, and it solves a surprising number of cases.

Q: Why does using 1.1.1.1 or 8.8.8.8 help?
Those are public DNS servers run by Cloudflare and Google, respectively. They are highly reliable, fast, and not subject to your ISP’s outages or filtering. Switching to them bypasses a broken local DNS configuration.

Q: Is it safe to use public DNS servers?
Yes, they are widely used and generally more secure than some ISP defaults. However, your DNS queries will be visible to the provider, so if privacy is a concern, look for a DNS service with a clear privacy policy or use DNS-over-HTTPS where supported.

Q: What does “Cannot resolve host” mean in the command line?
It’s the same error in a different form. Tools like ping or curl use the system’s DNS resolver. If they can’t find the IP, you’ll see that message. The fixes above apply exactly the same.

Q: Could this error be caused by a VPN?
Yes. A VPN changes your DNS servers to its own. If the VPN’s DNS is slow or blocked, you’ll get resolution failures. Try disconnecting the VPN and testing; if that works, reconnect and choose a different VPN server.

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