Knowledge Base

What is a 404 Error?

A 404 Not Found error is an HTTP status code indicating that the web server could not find the requested resource (e.g., a web page, image, video, or other file). This is displayed in the user's browser with a message such as "404 Not Found" or "Page Not Found". This error is usually caused by various reasons such as broken links, the page being deleted, or the URL being typed incorrectly.

What are the Most Common Causes of 404 Errors?

404 errors can have many causes. Here are some of the most common reasons:

• Misspelled URL: The user may have made a mistake when typing the web address into the browser.
• Broken Links: Links within or outside the website can break when the target page no longer exists.
• Page Deleted or Moved: The requested page may have been removed from the website or moved to a different URL.
• Server Issues: The server may be temporarily unavailable or experiencing DNS issues.
• Incorrectly Configured .htaccess File (Apache): Incorrect redirection rules in the .htaccess file can cause 404 errors.
• Plugin Conflicts (WordPress): In content management systems (CMS) such as WordPress, incompatibilities between plugins can lead to 404 errors.
• Domain Name DNS Issues: If there is a problem with the DNS records of the domain name, users may not be able to access the website and may receive a 404 error.

What are the Effects of 404 Errors on User Experience?

404 errors can have quite negative effects on user experience:

• User Dissatisfaction: Users are disappointed when they cannot find the information they are looking for.
• Increased Website Bounce Rate: Users often leave the website when they encounter a 404 error.
• Damage to Brand Image: A website that frequently encounters 404 errors creates a negative image in terms of reliability and professionalism.
• Decreased SEO Performance: Search engines may rank websites with a large number of 404 errors lower.

How Do I Detect 404 Errors?

There are various methods to detect 404 errors:

• Google Search Console: Google Search Console is a free tool you can use to detect 404 errors on your website. You can view 404 errors by reviewing the "Crawl Errors" report in the "Crawl" section.
• Website Analytics Tools (Google Analytics, etc.): Website analytics tools like Google Analytics can help you track which pages users are trying to access and which pages are returning 404 errors.
• Log Files: You can get detailed information about 404 errors by examining your web server's log files (such as which IP address, on what date, and for which page the error was received).
• Online 404 Error Checkers: There are many online 404 error checking tools available on the internet. These tools scan your website and detect 404 errors.
• User Feedback: Feedback from your users can help you identify 404 errors.

What Solutions Can I Apply to Fix 404 Errors?

You can apply the following solutions to fix 404 errors:

1. Check the URL: Carefully check the URL to see if users are typing it incorrectly.
2. Update Links: Identify and update broken links on your website. This applies to internal links (links between pages within your website) and external links (links to other websites).
3. Create Redirects: If a page has been moved or deleted, create a 301 (permanent) or 302 (temporary) redirect from the old URL to the new URL.
4. Create a Custom 404 Page: To prevent users from immediately leaving your website when they encounter a 404 error, create a user-friendly custom 404 page. On this page, you can offer helpful content such as a search bar, a link to the homepage, or links to popular pages.
5. Check the .htaccess File (Apache): Correct any incorrect redirection rules in the .htaccess file.
6. Check Plugins (WordPress): If you are using WordPress, check for incompatibilities between plugins and, if necessary, try to identify the source of the problem by disabling plugins.
7. Examine Server Logs: Analyze the server log files to analyze the causes of 404 errors and on which pages they occur in more detail.
8. Update the Sitemap: Update your website's sitemap (sitemap.xml) and submit it to search engines.

How to Create a Custom 404 Page?

Creating a custom 404 page can significantly improve user experience. Here's a step-by-step process for creating a custom 404 page:

1. 404 Page Design: Design a user-friendly and informative 404 page. This page may include the following elements:
   • Clear Message: A clear message such as "Page Not Found" or "Sorry, the page you are looking for does not exist."
   • Search Bar: A search bar to help users find the content they are looking for.
   • Link to Homepage: A link to your website's homepage.
   • Links to Popular Pages: Links to your website's most popular or important pages.
   • Contact Information: Contact information so users can reach you.
2. Creating the 404 Page (HTML): Create the 404 page you designed as HTML. For example:

   
       <!DOCTYPE html>
       <html lang="en">
       <head>
         <meta charset="UTF-8">
         <meta name="viewport" content="width=device-width, initial-scale=1.0">
         <title>404 - Page Not Found</title>
         <style>
           body {
             font-family: Arial, sans-serif;
             text-align: center;
             padding: 50px;
           }
           h1 {
             font-size: 3em;
             margin-bottom: 20px;
           }
           p {
             font-size: 1.2em;
             margin-bottom: 30px;
           }
           a {
             color: #007bff;
             text-decoration: none;
           }
           a:hover {
             text-decoration: underline;
           }
         </style>
       </head>
       <body>
         <h1>404 - Page Not Found</h1>
         <p>Sorry, the page you are looking for does not exist.</p>
         <p>You can try to find what you’re looking for using the links below:</p>
         <ul>
           <li><a href="/">Homepage</a></li>
           <li><a href="/contact">Contact</a></li>
           <li><a href="/blog">Blog</a></li>
         </ul>
       </body>
       </html>
       

3. Uploading the 404 Page to the Server: Upload the 404.html file you created to the root directory of your web server (usually public_html or www).
4. Configuring the .htaccess File (Apache): Redirect 404 errors to your custom 404 page using the .htaccess file. Add the following line to the .htaccess file:

   
       ErrorDocument 404 /404.html
       

5. Web Server Configuration (Other Servers): If you are using a web server other than Apache (e.g., Nginx), make the necessary changes in the server configuration file to redirect 404 errors to your custom 404 page.

How to Create a Custom 404 Page in WordPress?

There are several ways to create a custom 404 page in WordPress:

1. Editing Theme Files: Create a file named 404.php in your WordPress theme or edit the existing 404.php file. Add your custom 404 page design to this file.
2. Using a Plugin: You can easily create a custom 404 page by using WordPress plugins such as "Custom 404 Page" or "404page". These plugins usually offer a user-friendly interface and you don't need to write code.
3. Creating a Page and Redirecting: Create a page in WordPress and add your custom 404 page design to this page. Then, redirect 404 errors to this page using the .htaccess file or a plugin.

What is a Redirect and Why is it Used?

A redirect is the process of automatically redirecting a request made to one URL to another URL. Redirects are used to maintain user experience and improve SEO performance when you change the structure of your website, move pages, or delete them.

There are two basic types of redirects:

• 301 Redirect (Permanent Redirect): Indicates that a page has been permanently moved to a new URL. Search engines transfer the ranking of the old URL to the new URL.
• 302 Redirect (Temporary Redirect): Indicates that a page is temporarily redirected to another URL. Search engines retain the ranking of the old URL.

How to Create a Redirect?

There are different methods for creating a redirect:

• .htaccess File (Apache): You can create a redirect by adding rules to the .htaccess file as follows:

  
      # Redirect a single page
      Redirect 301 /old-page.html /new-page.html
  
      # Redirect a directory
      Redirect 301 /old-directory /new-directory
      

• PHP Code: You can also create a redirect using PHP:

  
      <?php
      header("Location: /new-page.html", true, 301);
      exit();
      ?>
      

• WordPress Plugins: WordPress plugins such as "Redirection" or "Yoast SEO Premium" make it easy to create redirects.

What is the Relationship Between 404 Errors and SEO?

404 errors can negatively affect SEO performance. Search engines may rank websites with a large number of 404 errors lower. In addition, 404 errors can negatively affect the user experience, increasing the bounce rate from your website, which can further worsen SEO performance.

Therefore, regularly checking and fixing 404 errors is important to protect your SEO performance.

What are the Ways to Prevent 404 Errors?

While it's impossible to completely eliminate 404 errors, you can take the following measures to reduce the likelihood of them occurring:

• Create Links Carefully: When creating links on your website, type URLs carefully and avoid errors.
• Regularly Check Links: Regularly check the links on your website and update them by identifying broken links.
• Create Redirects Before Moving or Deleting Pages: Before moving or deleting a page, create a 301 redirect from the old URL to the new URL or a relevant page.
• Keep the Sitemap Updated: Keep your website's sitemap (sitemap.xml) up to date and submit it to search engines regularly.
• Consider User Feedback: Take into account 404 error reports from your users and fix them quickly.

Important Note: Understanding the causes of 404 errors and implementing the correct solutions is critical to improving your website's user experience, increasing SEO performance, and protecting your brand image.

Real-Life Examples and Case Studies

Case Study 1: E-Commerce Site and Product Page 404 Errors

A large e-commerce site removed some old product pages while expanding its product range. However, they forgot to redirect the links to these product pages. As a result, users who clicked on these product pages in search engines encountered a 404 error. This negatively affected the website's traffic and sales. After realizing the situation, the site administrators created 301 redirects to the old product pages, solving the problem and improving their SEO performance.

Case Study 2: Blog Site and Category Change

A popular blog site changed some category names while updating its content strategy. However, they neglected to redirect the old category URLs to the new category URLs. This resulted in traffic from search engines and other websites resulting in 404 errors. To fix the 404 errors they detected in Google Search Console, the site administrators created 301 redirects from the old category URLs to the new category URLs. In this way, they prevented traffic loss and maintained their SEO performance.