When you're browsing the web, encountering a Site Not Found or 404 Not Found error can be frustrating. One of the most common causes of such errors, especially when trying to reach a website by domain name, is issues related to DNS (Domain Name System) settings. DNS acts as the phonebook of the internet, converting human-readable domain names into IP addresses, and allowing browsers to find the websites you're trying to visit. If something goes wrong with DNS resolution, it can result in a Site Not Found error.

This knowledgebase will cover various aspects of DNS, explain how it functions, and provide steps for resolving DNS-related issues that may cause a site to be unreachable.

Understanding DNS and Its Role

DNS is essentially the system that translates domain names (like www.example.com) into IP addresses (like 192.0.2.1). When you type a URL in your browser, your computer needs to communicate with a DNS server to translate that URL into an IP address that the network can understand. Without DNS, you'd need to memorize the numeric IP addresses of every site you want to visit.

Common Causes of DNS Errors

Several issues can arise with DNS that result in a site not being found:

• DNS Server Issues: The DNS server your computer is using may be down, misconfigured, or slow.
• Expired or Invalid DNS Records: Websites can experience issues if the DNS records (A records, CNAME records, etc.) aren’t correctly set or have expired.
• Wrong DNS Configuration: If the DNS settings on your computer or router are incorrect, you might not be able to resolve domain names properly.
• Propagation Delays: If you've recently changed your DNS settings or moved your website to a new host, the new DNS records might not have fully propagated across the global network of DNS servers.
• Firewall/Network Configuration Issues: Sometimes, firewalls or network security tools block DNS queries, causing your computer to fail to resolve domain names.

How DNS Works

To resolve the error, it helps to understand the steps DNS goes through to find a website:

1. Domain Query: When you enter a domain name in your browser, your device sends a DNS query to the configured DNS server.
2. Checking Local Cache: Before querying the external server, your device first checks its local cache. If it finds the IP address already stored, it uses that, which speeds up the process.
3. Recursive Query: If the address isn't cached, the DNS server queries other DNS servers, starting with the root DNS servers, followed by TLD (Top-Level Domain) servers, and then authoritative DNS servers for the specific domain.
4. Response: Once the authoritative DNS server is found, it responds with the IP address of the website, allowing your browser to make the connection.

Fixing DNS-Related Site Not Found Errors

Verify DNS Server Settings

The first step in troubleshooting DNS issues is ensuring that your DNS settings are configured correctly.

• Check Local DNS Settings on Your Computer:

  • On Windows, you can check the DNS settings by opening Network & Internet settings and inspecting the properties of your current network connection.
  • On macOS, go to System Preferences > Network > Advanced > DNS.
  • Make sure the DNS servers listed are appropriate (e.g., Google DNS 8.8.8.8, Cloudflare DNS 1.1.1.1, or your ISP’s DNS).

• Check Your Router’s DNS Settings: Many home routers have a default DNS configuration. Ensure that your router is set to use a reliable DNS service. You can change it to a public DNS like Google or Cloudflare if you're experiencing issues.

Clear DNS Cache

DNS information is cached locally on your device to speed up the process of domain resolution. Sometimes, this cache becomes outdated or corrupted, leading to a Site Not Found error.

• Windows: Open the Command Prompt and type:

   

  ipconfig /flushdns

  This command clears your DNS cache.

• macOS: Open the Terminal and type:

   

  sudo killall -HUP mDNSResponder

Check DNS Propagation

If you recently changed DNS records for your domain (for example, after migrating your website), it might take some time for those changes to propagate across all DNS servers worldwide. DNS propagation can take anywhere from a few hours to 48 hours.

• Check DNS Propagation: Use an online DNS propagation checker to see if your DNS changes have propagated globally. Tools like DNSChecker.org can help you track this.

Use a Different DNS Server

If you're still experiencing issues, try switching to a different DNS server to see if that resolves the problem. Sometimes, DNS servers may experience outages or delays, causing websites to be unreachable.

Popular public DNS servers include:

• Google DNS: 8.8.8.8 and 8.8.4.4
• Cloudflare DNS: 1.1.1.1 and 1.0.0.1
• OpenDNS: 208.67.222.222 and 208.67.220.220

Check the Domain’s DNS Records

If you manage your website and you’re getting a Site Not Found error, there might be an issue with your domain’s DNS records. To fix this, you’ll need to check the DNS records for your domain:

• A Record: This is the primary record that points your domain to an IP address. Make sure the IP address in your A record matches the server where your website is hosted.
• CNAME Record: If you use subdomains, check that the CNAME records are set up correctly.
• TTL (Time to Live): Ensure the TTL is set to a reasonable value, so DNS changes propagate faster.

You can view your domain’s DNS records using online tools like MXToolbox.

Check for Firewall or Security Software Interference

If you have a firewall or security software running, it might block DNS queries or manipulate the results. Disable the firewall temporarily to check if the issue persists. Additionally, check if any VPN or proxy services you are using could be affecting DNS resolution.

 Restart Devices

Sometimes, the simplest solution is to restart your devices. Restart your computer, router, and modem to reset the network connection and clear any temporary issues that might be affecting DNS resolution.

Contact Your Hosting Provider or ISP

If you've gone through all the steps above and are still facing issues, the problem may be at your hosting provider’s or ISP's end. Contact their customer support for assistance, and they may be able to resolve DNS-related issues on their servers.

Preventing Future DNS Issues

To avoid future "Site Not Found" errors, here are some proactive steps you can take:

• Choose a Reliable DNS Provider: Opt for a reliable DNS service with high uptime and fast response times, such as Google DNS or Cloudflare DNS.
• Set Up DNS Monitoring: Regularly monitor your domain’s DNS records to ensure they’re accurate and up to date.
• Enable DNSSEC: Domain Name System Security Extensions (DNSSEC) add a layer of security to prevent DNS attacks, like cache poisoning.
• Minimize DNS Changes: Avoid frequently changing your DNS settings unless necessary. Each DNS change can increase the risk of errors or misconfigurations.
• Use Redundant DNS Servers: Consider setting up secondary DNS servers to ensure redundancy in case the primary DNS server goes down.

Usage Field:

The usage field refers to various scenarios where a user encounters the Site Not Found error while accessing websites. This can affect individual users trying to access their favorite websites, website administrators troubleshooting issues with site availability, or network administrators managing DNS configuration for large networks. This knowledgebase provides solutions to these common DNS-related issues, and it applies to:

• Home Users: Resolving DNS errors that prevent access to websites.
• Website Administrators: Diagnosing and fixing DNS misconfigurations that cause users to see a Site Not Found error.
• Network Administrators: Ensuring that DNS servers are correctly configured within organizations.
• IT Support Teams: Assisting clients or end-users in resolving DNS issues that cause website unavailability.

By properly configuring and managing DNS, users and IT professionals can significantly reduce the chances of encountering the "Site Not Found" error and ensure smooth access to websites.

Technical Issue: DNS-Related Site Not Found Error

A Site Not Found error related to DNS generally indicates that your browser is unable to resolve the domain name to an IP address through DNS. DNS issues can arise due to a variety of reasons, such as misconfigured DNS settings, server failures, or issues with domain name registration. Here are some of the main technical issues that can cause this error:

1. DNS Server Misconfiguration: The DNS server you're using may not be able to resolve domain names correctly due to misconfigurations, outdated information, or issues with the server itself.

2. Corrupted or Outdated DNS Cache: Your device might be storing outdated or corrupt DNS information, preventing proper domain resolution and causing errors when trying to access websites.

3. ISP DNS Server Issues: Sometimes, your ISP’s DNS servers may experience outages or disruptions that prevent the successful resolution of domain names.

4. Incorrect DNS Settings: Manual DNS configurations might be incorrect, leading to issues when your system tries to resolve domain names.

5. Domain Expiration: A domain’s registration may have expired, and the associated DNS records may no longer be valid.

6. DNS Propagation Delays: When a domain's DNS records are updated, it can take some time for those changes to propagate across DNS servers globally. During this period, some users might experience Site Not Found errors.

7. Firewall or Security Software Interference: Firewalls or antivirus software can block DNS requests or certain websites, causing resolution failures.

8. Network Connectivity Issues: Sometimes, connectivity issues within your local network or internet service can prevent successful DNS queries.

Technical FAQ: Fix Site Not Found Errors Using Correct DNS

Here are 10 frequently asked questions (FAQ) related to fixing the Site Not Found error using the correct DNS configuration:

What is DNS, and how does it relate to the Site Not Found error?

Answer:
DNS (Domain Name System) is responsible for translating domain names (e.g., www.example.com) into IP addresses (e.g., 192.168.1.1). If your computer can't resolve a domain name into an IP address because of DNS issues, you will encounter a "Site Not Found" error. This typically happens when the DNS server is unavailable, misconfigured, or has outdated information.

How do I know if the DNS issue is the cause of the error?

Answer:
You can verify if the issue is DNS-related by performing a few tests. Use tools like nslookup or dig to check if your DNS server is resolving domain names properly. If these tools fail to resolve a domain name into an IP address, you are likely experiencing DNS issues.

How can I clear my DNS cache to fix this error?

Answer:
Clearing your DNS cache can help resolve issues with outdated or corrupt information. The process varies depending on your operating system:

• Windows: Open the Command Prompt and type ipconfig /flushdns.
• macOS: Open Terminal and type sudo killall -HUP mDNSResponder.
• Linux: Use the appropriate command based on your distribution, such as sudo systemd-resolve --flush-caches for Ubuntu.

What DNS servers should I use to fix the "Site Not Found" error?

Answer:
Using reliable public DNS servers can help resolve the error. Some recommended DNS servers are:

• Google DNS: 8.8.8.8 and 8.8.4.4
• Cloudflare DNS: 1.1.1.1 and 1.0.0.1
• OpenDNS: 208.67.222.222 and 208.67.220.220

These DNS servers are generally more reliable and faster than default ISP DNS servers.

How can I check if my DNS server is down?

Answer:
To check if your DNS server is down, try using tools like nslookup or dig. Open Command Prompt (Windows) or Terminal (macOS/Linux) and enter:

• nslookup www.example.com
• If it fails to resolve, your DNS server might be down or misconfigured.

Alternatively, you can try using a different DNS server, like Google DNS or Cloudflare DNS, and see if the issue persists.

Why does DNS propagation take so long?

Answer:
DNS propagation can take anywhere from a few hours to 48 hours because DNS information is cached by multiple DNS servers across the internet. When you update DNS records (e.g., switching hosting providers), it can take time for these changes to propagate across the global network of DNS servers. During this time, some users might see outdated DNS information, causing "Site Not Found" errors.

How do I fix issues with domain expiration causing DNS resolution failures?

Answer:
If the domain has expired, you need to renew the domain registration with the domain registrar. You can check the domain’s registration status using Whois lookup tools, such as Whois.com. Once the domain is renewed, the DNS records will be active again, and the error should be resolved.

How do I change my DNS settings on Windows to fix the error?

Answer:
To change your DNS settings on Windows:

1. Open Control Panel → Network and Sharing Center → Change adapter settings.
2. Right-click on your active network connection and select Properties.
3. Click on Internet Protocol Version 4 (TCP/IPv4) and then click Properties.
4. Select Use the following DNS server addresses and enter a reliable DNS server like Google DNS (8.8.8.8, 8.8.4.4) or Cloudflare DNS (1.1.1.1, 1.0.0.1).

How do I check for DNS misconfiguration if I am a website administrator?

Answer:
As a website administrator, check your domain's DNS records for misconfigurations:

1. Ensure the A record points to the correct IP address of your server.
2. Check CNAME records for any necessary subdomains.
3. Verify MX records for email configuration (if applicable).
4. Use online tools to inspect DNS settings for any discrepancies.

Can security software or firewalls block DNS resolution?

Answer:
Yes, firewalls or security software can block DNS queries or certain websites. If you're encountering the Site Not Found error, try disabling your firewall or security software temporarily to see if the issue persists. If disabling the software resolves the issue, you may need to adjust your firewall’s settings to allow DNS queries.