When a WordPress website suddenly stops working, shows a blank page, displays a broken layout, or returns a 500 Internal Server Error, the cause isn't always immediately obvious.
Siteligent's diagnostic tools can be used together to narrow down the problem. A practical troubleshooting process is to start with caching, then check debug logs and PHP errors, identify the problematic plugin or code, and finally address database or broken-link issues where relevant.
Step 1: Clear All Caches
If the website started showing a blank page, broken styling, or an incorrect layout after an update or configuration change, start by clearing the site's caches.
Go to the site's Cache tab and select Clear All Caches.
This clears the supported caching layers detected by Siteligent, including supported caching plugins and hosting-level caches.
After clearing the caches, open your website in an incognito/private browser window and check the affected page again.
This helps determine whether the problem was caused by an outdated cached version of the page or its assets.
If the website is working normally after clearing the cache, there may not be a code or plugin problem at all.
Step 2: Enable Debug Mode and Check the Logs
If clearing the cache doesn't resolve the problem, the next step is to look for a PHP or WordPress error.
Open your site's Toolkit settings and turn Debug Mode on. Siteligent safely configures the necessary WordPress debugging settings in wp-config.php.
Then open the Debug Log Viewer and review the latest entries.
If the log is empty, reproduce the problem first:
Open the affected page.
Perform the action that causes the error.
Return to the Debug Log Viewer.
Refresh the log.
This gives WordPress an opportunity to write the error to wp-content/debug.log. Look for errors that appeared at approximately the same time the problem occurred.
Pay particular attention to the file path, plugin or theme name, error message, and line number.
Step 3: Analyze the Error with Zyra AI
Once you've found an error, you can use Siteligent's PHP Error Monitor and Zyra AI to help understand it.
Locate the relevant error in the PHP Error Monitor, or use the information from the Debug Log Viewer.
Select Analyze to have the AI analyze the error.
Zyra AI can examine the error's file context and help determine whether it originated from:
WordPress Core
A plugin
A parent theme
A child theme
Custom code
For example, if the error points to a directory such as: wp-content/plugins/query-monitor/ that provides a strong indication that the problem is associated with that plugin.
Review the Fix Steps provided by the AI before making changes. The analyzer is designed to turn technical error information into practical troubleshooting steps, including relevant files, line numbers, variables, and code context where available.
Step 4: Deactivate or Update the Problematic Plugin
If you've identified a plugin as the likely cause, temporarily deactivate it to determine whether it restores the website.
From the Plugins manager in Siteligent:
Locate the plugin identified in the error.
Click Deactivate.
Check the website again.
If the site starts working, the plugin is likely involved in the problem.
Check whether a newer version of the plugin is available.
If an update is available, install the official update.
Reactivate the plugin and test the website again.
Avoid directly editing files inside a third-party plugin as a permanent solution. Plugin updates can overwrite those changes.
If the problem is caused by custom code or a child theme, the appropriate fix may be different.
Step 5: Clean Up and Optimize the Database
If the website is experiencing slow page loads or database-related performance problems, review the site's database diagnostics.
Go to the site's Database diagnostics and consider running:
Expired Transients
Optimize Tables
These operations can remove expired temporary data and reclaim unused database space where applicable.
For production sites, create a database backup before performing database optimization.
Siteligent processes database cleanup in controlled batches to reduce the risk of long-running operations consuming excessive server resources.
Step 6: Find and Fix Broken Links
If visitors are receiving 404 errors, the problem may be caused by links pointing to pages that no longer exist.
Open Siteligent's Broken Link Checker and review the reported broken URLs. The checker can identify the content containing the broken link, allowing you to locate the source post or page.
Once you've found the source:
Open the direct edit link for the affected post or page.
Update or remove the broken link.
If the original URL has permanently moved, use the Redirects Manager to create a redirect.
Run another check to confirm the issue has been resolved.
For a permanently moved page, a 301 redirect can send visitors from the old URL to the new location.
A Complete Troubleshooting Workflow
For a website that suddenly develops an error, you can work through the diagnostics in this order:
Clear All Caches and test the website again.
Enable Debug Mode if the problem remains.
Check the Debug Log Viewer for newly generated errors.
Review PHP Error Monitor for captured runtime errors.
Analyze the error with Zyra AI to identify the likely source and recommended fix.
Deactivate the suspected plugin if a plugin is identified as the cause.
Update the plugin or theme if an official fix is available.
Review database diagnostics if the problem involves performance or database behavior.
Check Broken Link Checker if visitors are encountering 404 errors.
Create redirects where URLs have permanently moved.
This approach helps you move from the visible symptom to the underlying cause instead of making several unrelated changes at once.