WordPress errors can disrupt your site’s functionality and user experience. This guide covers advanced troubleshooting for common issues like HTTP 500 errors, database connection failures, white screen of death, and plugin conflicts, all using cPanel tools.
Error 1: HTTP 500 Internal Server Error
Symptoms:
- Blank page or “Internal Server Error.”
 
Causes:
- Corrupt 
.htaccessfile - PHP memory limit exceeded
 - Plugin/theme conflict
 
Fix:
- Check Error Logs in cPanel:
- Navigate to Metrics → Errors.
 
 - Rename 
.htaccessvia File Manager:- Change to 
.htaccess_oldand reload site. 
 - Change to 
 - Increase PHP memory limit:
- Go to MultiPHP INI Editor → 
memory_limit = 256M. 
 - Go to MultiPHP INI Editor → 
 - Disable plugins:
- Rename 
wp-content/pluginstoplugins_old. 
 - Rename 
 
Error 2: Error Establishing Database Connection
Symptoms:
- Site shows database connection error.
 
Causes:
- Incorrect DB credentials in 
wp-config.php - MySQL service down
 
Fix:
- Verify credentials in 
wp-config.php:
 - Check database in phpMyAdmin.
 - Restart MySQL (requires root access or contact host).
 
Error 3: White Screen of Death
Symptoms:
- Completely blank page.
 
Causes:
- PHP errors hidden
 - Plugin/theme conflict
 
Fix:
- Enable debugging in 
wp-config.php:
 - Check 
wp-content/debug.logfor errors. - Disable plugins/themes as in Error 1.
 
Error 4: Mixed Content After SSL
Symptoms:
- Site loads with insecure elements.
 
Fix:
- Update URLs:
- Use Search Replace DB or WP-CLI:
 
 - Use Search Replace DB or WP-CLI:
 - Install Really Simple SSL plugin.
 
Error 5: Memory Exhausted
Symptoms:
- Fatal error: Allowed memory size exhausted.
 
Fix:
- Increase memory limit in 
wp-config.php:
 - Adjust in MultiPHP INI Editor.
 
Advanced Debugging
- Enable PHP error reporting:
 - Use SSH to tail logs:
 
Security Best Practices
- Always back up before troubleshooting.
 - Use staging environment for testing fixes.
 - Keep WordPress core, themes, and plugins updated.