Common PrestaShop Errors & How to Fix Them

PrestaShop is a powerful eCommerce platform, but like any software, it can encounter errors that disrupt store performance. Whether you’re facing a 500 Internal Server Error, 404 Page Not Found, or slow loading times, troubleshooting these issues quickly is crucial. In this guide, we’ll cover the most common PrestaShop errors and provide step-by-step solutions to resolve them.For more details, check the official PrestaShop troubleshooting guide.

1. 500 Internal Server Error

Issue:

This error appears when there’s a problem with the server, often after a module installation, an update, or a misconfiguration.

Solution:

Enable Debug Mode:

1. Open FTP and navigate to: /config/defines.inc.php
2. Find the line: define('_PS_MODE_DEV_', false);
3. Change it to: define('_PS_MODE_DEV_', true);
4. Reload your website to see a detailed error message.

Increase PHP Memory Limit: Edit the .htaccess file and add:

php_value memory_limit 256M

Check Server Logs and disable newly installed modules if needed.

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2. 404 Page Not Found Error

Issue:

Product, category, or CMS pages return a 404 error after an update or migration.

Solution:

Regenerate .htaccess File:

1. Navigate to Shop Parameters → Traffic & SEO.
2. Scroll down and click Save to regenerate the .htaccess file.

Enable Friendly URLs:

1. Go to Shop Parameters → Traffic & SEO.
2. Disable and re-enable Friendly URL settings.

Clear Cache: Delete files from:

/var/cache/prod/
/var/cache/dev/

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3. 504 Gateway Timeout Error

Issue:

Your site takes too long to load and eventually times out, commonly caused by slow servers or large database queries.

Solution:

Increase PHP Execution Time: Edit .htaccess and add:

php_value max_execution_time 300

Optimize Database: Run these SQL commands in phpMyAdmin:

OPTIMIZE TABLE ps_connections;
OPTIMIZE TABLE ps_guest;
OPTIMIZE TABLE ps_cart;

Use a CDN (Content Delivery Network) to speed up page loading.

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4. Admin Dashboard Not Loading

Issue:

Unable to access Back Office after a module installation or PrestaShop update.

Solution:

Rename Admin Folder:

1. Open FTP and go to your PrestaShop directory.
2. Rename /admin/ to /admin123/.
3. Access the new URL: https://yourwebsite.com/admin123.

Clear Cache via FTP: Delete files inside:

/var/cache/prod/
/var/cache/dev/

Disable Faulty Modules via Database:

1. Open phpMyAdmin and locate ps_module table.
2. Find the faulty module and change active from 1 to 0.

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5. White Screen of Death (WSOD)

Issue:

A blank screen appears with no error message, usually after an update or theme modification.

Solution:

Enable Debug Mode (follow the steps in the 500 Internal Server Error solution).

Check PHP Version: Ensure your server runs PHP 7.4 or 8.1, as older versions may cause conflicts.

Disable Non-Compatible Modules using FTP or phpMyAdmin.

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Final Thoughts

Troubleshooting PrestaShop errors can be frustrating, but with the right approach, most issues can be fixed quickly. Always keep backups, update modules carefully, and optimize your store for better performance.

Need expert help? Contact us for professional PrestaShop support! Re-engagement — objectives. As developers, we rightfully obsess about the customer experience, relentlessly working to squeeze every millisecond out of the critical rendering path, optimize input latency, and eliminate jank. At the limit, statically generated, edge delivered, and HTML-first pages look like the optimal strategy. That is until you are confronted with the realization that the next step function in improving conversion rates and business.