WordPress Troubleshooting Guide 2026

Published April 21, 2026

WordPress Troubleshooting Guide

WordPress problems usually fall into a small number of categories: plugin conflicts, theme issues, server errors, and database problems. A systematic approach resolves most issues in minutes.

The Troubleshooting Mindset

Before changing anything, note exactly what you see — the error message, which pages are affected, and what changed recently. Recent changes (plugin installs, updates, code edits) are the most common cause of new problems.

Step 1: Enable Debug Mode

Add these lines to wp-config.php to see PHP errors:

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);

Check /wp-content/debug.log for error details. Disable debug mode on production once the issue is resolved.

Step 2: Isolate the Cause

• Deactivate all plugins, then reactivate one by one to find the conflict
• Switch to a default theme (Twenty Twenty-Five) to test for theme issues
• Check if the problem occurs when logged out — some issues only affect logged-in users

Step 3: Check Server Resources

Many WordPress errors stem from resource limits. Check your PHP memory limit, execution time, and disk space. SiteICO's dashboard shows real-time resource usage for your site.

Step 4: Review Recent Changes

Check your activity log for recent plugin installs, theme changes, or settings modifications. Roll back to your last known good state using SiteICO's backup restore if needed.

Common Error Categories

• White screen of death: PHP fatal error — enable debug mode
• 500 Internal Server Error: Server misconfiguration or PHP crash
• Database connection error: Wrong credentials or database server down
• Login redirect loop: Cookie or HTTPS configuration issue