WordPress troubleshooting-white screen, errors, and common issues

WordPress can develop problems after updates, plugin conflicts, or server configuration changes. Most issues can be diagnosed and fixed by enabling debug mode, checking logs, and methodically disabling plugins to isolate the cause.

White screen of death (WSOD)

White screen means a fatal PHP error occurred but isn't displaying. Causes: memory exhaustion, plugin conflict, or incompatible PHP version.

First step: Enable debug logging (see below). This logs errors to wp-content/debug.log where you can see the actual problem.

Enable WordPress debug mode

Edit wp-config.php and add these lines above "That's all, stop editing!":

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

Then check the error log:

tail -100 /home/username/public_html/wp-content/debug.log

The log will show which line caused the fatal error.

Memory limit errors

Error: "Fatal error: Allowed memory size exhausted"

Increase memory in wp-config.php:

define('WP_MEMORY_LIMIT', '256M');
define('WP_MAX_MEMORY_LIMIT', '512M');

For shared hosting, use cPanel Select PHP Version → PHP Options to increase memory_limit.

Disable plugins to isolate conflicts

Safe mode: Temporarily disable all plugins without accessing WordPress admin:

1. Connect via FTP or File Manager
2. Navigate to wp-content/plugins/
3. Rename it to plugins-old
4. Try loading your site
5. If it works, a plugin caused the error
6. Rename it back to plugins/
7. Rename each plugin folder individually (add -off) to find the culprit

Admin login issues

Stuck at login page or login button doesn't work:

• Clear browser cookies and cache (Ctrl+Shift+Delete)
• Try incognito/private browser window
• Reset password via FTP: Delete or rename wp-login.php-old file
• Check if HTTPS is enforced in wp-config.php

Database connection errors

Error: "Error establishing database connection"

Causes: Wrong credentials, database server offline, or file permissions.

Fix:

1. Verify credentials in wp-config.php match cPanel database user
2. Test MySQL is running: systemctl status mysql
3. Check if database exists: mysql -u user -p -e "SHOW DATABASES;"
4. Verify database user has permissions to that specific database

WordPress troubleshooting checklist

• ☐ Enable WP_DEBUG and check wp-content/debug.log
• ☐ Increase WP_MEMORY_LIMIT to 256M
• ☐ Disable all plugins (rename plugins folder to plugins-old)
• ☐ Switch to default WordPress theme (if custom theme causing issue)
• ☐ Check PHP version compatibility (7.4+ recommended)
• ☐ Clear browser cache (Ctrl+Shift+Delete)
• ☐ Check if database connection credentials are correct
• ☐ Review WordPress error logs via cPanel File Manager
• ☐ Check system resources: is server out of memory or disk space?
• ☐ If recent update caused issue, consider restoring backup

Related: WordPress backups | Memory limit errors | PHP fatal errors

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