When you try to load a website, your computer relies on the Domain Name System (DNS) to translate the human-readable domain name (like example.com) into a machine-readable IP address (like 192.0.2.1). If DNS resolution fails, your browser will display errors like "DNS_PROBE_FINISHED_NXDOMAIN" or "Server IP address could not be found."

DNS problems can arise at the local computer level, the router level, the ISP level, or the website host level. In this guide, we will walk you through standard diagnostic procedures to troubleshoot and fix DNS errors on your device.

1. Perform a Hard Refresh & Test the Live Status

Before deep diving into settings, rule out temporary browser glitches. Force a hard refresh (Ctrl + F5 on Windows/Linux or Cmd + Shift + R on macOS) to bypass your browser's local cache. Next, check the website on our homepage to see if it is down for everyone or just you. If it is up, the issue is local to your device, network, or DNS configuration.

2. Flush Your Local DNS Cache

Operating systems save previously resolved domain-to-IP mappings in a local cache to speed up web requests. If a website changes its server IP address, your system might still try to connect to the old, cached IP, causing connection failures.

You can force your operating system to clear this cache by running a simple terminal command:

On Windows:

  1. Open the Start Menu, search for Command Prompt, right-click it, and select Run as Administrator.
  2. Type the following command and press Enter: 
    ipconfig /flushdns
  3. You should see a message confirming: "Successfully flushed the DNS Resolver Cache."

On macOS:

  1. Open Terminal (located in Applications > Utilities).
  2. Type the following command and press Enter: 
    sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
  3. Enter your administrator password when prompted.

On Linux:

  1. Open a terminal window.
  2. If your system uses systemd-resolved (common in Ubuntu/Debian), run: 
    sudo resolvectl flush-caches

3. Change Your DNS Servers to Public Resolvers

By default, your home router is configured to use the DNS servers provided by your Internet Service Provider (ISP). ISP DNS servers can sometimes be slow, unstable, or prone to downtime. Switching your device or router to use free, public DNS resolvers from Google or Cloudflare can immediately solve access problems.

Recommended Public DNS IP Addresses:

  • Cloudflare DNS: Primary 1.1.1.1 | Secondary 1.0.0.1 (Fast and privacy-focused)
  • Google Public DNS: Primary 8.8.8.8 | Secondary 8.8.4.4 (Highly reliable and globally distributed)

How to change DNS settings on Windows:

  1. Open the Control Panel and go to Network and Sharing Center > Change adapter settings.
  2. Right-click your active connection (Wi-Fi or Ethernet) and choose Properties.
  3. Select Internet Protocol Version 4 (TCP/IPv4) and click Properties.
  4. Choose Use the following DNS server addresses, enter the Cloudflare or Google IPs, and click OK.

4. Check Your Local Hosts File

The hosts file is a local plain-text file that maps hostname strings directly to IP addresses, overriding DNS settings. If a malware infection or manual edit added a line mapping a domain to an incorrect or local loopback IP (like 127.0.0.1), that website will fail to load.

  • Windows Path: C:\Windows\System32\drivers\etc\hosts
  • macOS/Linux Path: /etc/hosts

Open this file with administrator privileges in a text editor (like Notepad or Nano). Check if there are any lines mentioning the domain you are trying to access. If so, remove them, save the file, and refresh your browser.