• Neeraj Chaturvedi
• August 25, 2024
• Comments
• PHP Web Development Website WordPress WordPress Automation

Fixing WordPress Issues After Moving to a Server with PHP 8

Problem: Why does my WordPress site break and prevent admin access after moving to a new server with PHP 8?

I’ve moved my WordPress site to a new server with PHP 8, but now the website breaks, and I can’t access the admin panel.

Solution:

When moving to a new server with PHP 8, WordPress sites, especially those with older themes, plugins, or custom code, can experience compatibility issues. Here’s a step-by-step guide to troubleshoot and resolve the problem:

1. Check PHP Compatibility:

• Issue: Older WordPress versions, themes, and plugins might not be fully compatible with PHP 8. Functions deprecated in PHP 7 may cause fatal errors.
• Solution: Upgrade WordPress, themes, and plugins to the latest versions. Ensure all components are PHP 8 compatible.

2. Enable Debugging to Identify Errors:

• Add the following code to your wp-config.php file:
  

  define('WP_DEBUG', true);
  define('WP_DEBUG_LOG', true);
  define('WP_DEBUG_DISPLAY', false);
• The debug log (wp-content/debug.log) will show specific errors, helping you pinpoint incompatible code.

3. Replace Deprecated Code:

• If your theme or plugins contain outdated functions like create_function() or get_magic_quotes_gpc(), replace them with updated alternatives. You may need to edit custom code or consult developers for fixes.

4. Switch to a Default Theme:

• If you’re locked out of the admin, switch to a default theme (like Twenty Twenty-Three) by renaming your active theme folder via FTP. This will force WordPress to fall back to the default theme.

5. Disable All Plugins:

• Use FTP to rename the wp-content/plugins folder. If this resolves the issue, re-enable plugins one by one to find the problematic one.

6. Use a PHP Compatibility Plugin:

• Tools like PHP Compatibility Checker can scan your site and identify potential compatibility issues.

7. Roll Back to a Stable PHP Version:

• If the issues persist and can’t be resolved immediately, consider downgrading to PHP 7.4 temporarily until you update incompatible components.