A 404 error (Not Found) is one of the most common issues encountered on the web. It occurs when a user tries to access a page or resource that the server cannot locate. While the website itself may be working perfectly, the specific content being requested is missing, moved, or inaccessible.
Below is a detailed explanation of why 404 errors happen, how they affect your website, and how to properly fix and prevent them.
What is a 404 Error?
A 404 error is an HTTP status code that means the server was successfully reached, but it could not find the requested page. In simple terms:
The server is working
The connection is successful
But the page does not exist at that location
You may see messages like:
404 Not Found
Page Not Found
The requested URL was not found on this server
Common Causes of a 404 Error
1. Incorrect URL (Human Error)
One of the most frequent causes is a simple typo in the URL.
Examples:
Misspelling a page name
Using the wrong file extension (e.g., .html instead of .php)
Adding extra characters or slashes
Even a small mistake can lead to a 404 response.
2. Deleted or Removed Content
If a page, image, or file has been deleted from the server but users still try to access it, a 404 error will occur.
This often happens when:
Old blog posts are removed
Files are cleaned up without updating links
Content is accidentally deleted
3. Page or File Was Moved
Sometimes content is not deleted but moved to a new location without proper redirection.
For example:
/blog/post1 → /articles/post1
/old-page.html → /new-page.html
If no redirect is set up, users trying the old URL will get a 404 error.
4. Broken or Outdated Links
A broken link points to a page that no longer exists.
This can occur:
Within your own website (internal links)
From external websites linking to your content
From search engine results that haven’t been updated
5. DNS or Domain Configuration Issues
If your domain is not properly configured, some pages may not resolve correctly.
Possible issues include:
Incorrect DNS records
Domain not fully propagated
Subdomain misconfiguration
6. Missing Files on the Server
If the requested file does not physically exist in the server directory, a 404 error will be returned.
For example:
File not uploaded
Wrong directory placement (not in public_html)
File renamed but links not updated
7. Incorrect File Permissions
If permissions are too restrictive, the server may not be able to access the file.
Typical correct permissions:
Files: 644
Folders: 755
Incorrect permissions can make files appear “missing,” leading to a 404 error.
8. Misconfigured .htaccess File
The .htaccess file controls URL rewriting and redirects on many servers.
Errors in this file can:
Redirect users to non-existent pages
Block access to valid files
Create infinite rewrite loops
9. CMS Issues (e.g., WordPress)
Content Management Systems can generate 404 errors due to internal configuration problems.
Common causes:
Broken permalinks
Disabled or conflicting plugins
Theme issues
Corrupted database entries
10. Server or Application Routing Errors
For modern applications like Node.js or frameworks (e.g., Next.js), routing is handled dynamically.
A 404 error can occur if:
Routes are not properly defined
Backend API endpoints are missing
Deployment did not include all routes
Impact of 404 Errors
1. Poor User Experience
Visitors may leave your site if they cannot find what they’re looking for.
2. SEO Problems
Search engines like Google may:
De-rank your pages
Remove broken URLs from search results
Reduce site credibility
3. Loss of Traffic and Conversions
Broken pages can result in:
Lost leads
Reduced sales
Lower engagement
How to Fix a 404 Error
1. Verify the URL
Always start by checking if the URL is correct.
2. Restore Missing Content
If the page was deleted accidentally:
Restore it from backup
Re-upload the file
3. Set Up Redirects (301 Redirect)
Redirect old URLs to new ones so users don’t hit a dead end.
Example:
/old-page → /new-page
4. Fix Broken Links
Update:
Internal links
Navigation menus
External backlinks (if possible)
5. Check File Location
Ensure the file exists in the correct directory:
Typically public_html in DirectAdmin
6. Review .htaccess File
Correct rewrite rules
Remove conflicting entries
Test by temporarily renaming the file
7. Reset CMS Permalinks
For WordPress:
Go to Settings → Permalinks
Click Save Changes
8. Check Permissions
Set proper file and folder permissions.
9. Clear Cache
Sometimes cached data causes 404 errors:
Browser cache
CDN cache
Server cache
10. Check Server Logs
Logs provide detailed error information and can help identify the root cause.
How to Prevent 404 Errors
Regularly audit your website for broken links
Use redirects when moving or deleting pages
Maintain proper file organization
Monitor website changes carefully
Use tools like Google Search Console to detect errors
Create a custom 404 page to guide users back to useful content
A 404 error simply means that a requested page cannot be found, but the reasons behind it can vary widely—from simple typos to complex server misconfigurations. Understanding these causes allows you to quickly diagnose and fix the issue.
By properly managing your website structure, maintaining links, and using redirects where necessary, you can minimize 404 errors and ensure a smoother experience for your users.