A 404 error after saving permalinks in WordPress usually indicates an issue with the .htaccess file or your server’s URL rewriting settings. This is a common issue related to how WordPress handles “pretty permalinks” (URLs like /blog/post-name instead of ?p=123).

Let’s break down the main causes and how to fix them:

✅ 1. Missing or Incorrect .htaccess File (for Apache Servers)

When you change permalinks, WordPress tries to update the .htaccess file automatically. If it can’t, your URLs won’t work correctly, leading to 404 errors.

🔧 Solution:

• Go to your site’s root directory via FTP or File Manager.
• Check for a file named .htaccess.
• If it’s missing or empty, create/edit it and add the default WordPress rewrite rules:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress