如何向config.php添加数据库用户？Joomla后台404问题求助

Hey there! Let's break down your two issues and walk through solutions step by step. First, let's address that 404 error when accessing the Joomla admin, then we'll cover updating the database user in your config.php.

First, a critical note: PHP 4.0.10.18 is extremely outdated—Joomla 3.6.5 requires a minimum of PHP 5.3.10. This version mismatch is likely causing a lot of underlying issues, including potential compatibility problems with core Joomla files. I strongly recommend upgrading your PHP version first if possible, as it'll resolve many unexpected errors.

That said, let's go through common fixes for the 404 admin error:

• Update your config.php file with the new domain
  Joomla stores your site's base URL in configuration.php (sometimes renamed to config.php for security). You'll need to edit these values:

  public $live_site = 'https://your-new-domain.com'; // Replace with your actual new domain
  public $host = 'your-new-domain.com';
  

  Make sure there are no trailing slashes at the end of the URL.

• Check your .htaccess file (if using SEF URLs)
  If you have Search Engine Friendly URLs enabled, your .htaccess file might have rules tied to the old domain. Open it and:

  • Ensure the RewriteBase line points to your site's root (e.g., RewriteBase / if your Joomla is in the root folder)
  • Remove any lines that explicitly reference your old domain
  • If you don't have a .htaccess file, rename the htaccess.txt file in your Joomla root to .htaccess and set up SEF URLs once you regain access.

• Clear Joomla's cache manually
  Since you can't access the admin, delete cache files directly via FTP or your hosting control panel's file manager:

  • Navigate to your-joomla-root/tmp/ and delete all files/folders inside
  • Navigate to your-joomla-root/cache/ and delete all files/folders inside
    This will clear any cached references to the old domain.

• Verify server file permissions
  Ensure the /administrator/ folder and its files have correct permissions (typically 755 for folders, 644 for files). Incorrect permissions can cause the server to block access to the admin index.php file.

Joomla's config.php (or configuration.php) stores all database connection details. To update the database user, follow these steps:

1. Locate the configuration.php file in your Joomla root folder (it might be renamed to config.php for security).
2. Open it with a text editor (via FTP or your hosting control panel's file manager).
3. Look for these database-related lines:

   public $dbtype = 'mysql'; // Usually mysql or mysqli
   public $host = 'localhost'; // Your database host (often localhost)
   public $user = 'your-old-db-user'; // Replace with your new database username
   public $password = 'your-db-password'; // Update with the user's password
   public $db = 'your-database-name'; // Your database name
   public $dbprefix = 'jos_'; // Your Joomla table prefix (don't change this unless you know what you're doing)
   

4. Replace the $user value with your new database username, and update $password if the password has changed.
5. Save the file and upload it back to your server (if editing locally).

Important: Make sure the database user has full permissions (SELECT, INSERT, UPDATE, DELETE, CREATE, ALTER, DROP) for your Joomla database—otherwise, Joomla won't be able to connect properly.

内容的提问来源于stack exchange，提问作者trevor