Joomla error messages: complete troubleshooting guide

Joomla is a powerful CMS, but can sometimes show error messages. In this guide, we cover the most common Joomla errors.

1. White Screen of Death

Symptom

Your website shows only a white screen without error message.

Cause

• PHP error in extension or template
• Memory limit reached
• Corrupt files

Solution

1. Enable error display - In configuration.php: $error_reporting = "maximum";
2. Rename extension folders - Via FTP in /administrator/components/
3. Check PHP version - Joomla 4 requires PHP 7.2.5+
4. Restore backup - If nothing works

2. Error displaying the error page

Symptom

Double error message: error displaying the error page.

Cause

• Error template is corrupt
• Configuration problem
• Database connection failed

Solution

1. Check configuration.php - Database credentials correct?
2. Restore error.php - Copy from fresh Joomla installation
3. Clear cache - Via FTP: delete /cache/ contents

3. 500 - An error has occurred

Symptom

Generic 500 error on frontend or backend.

Cause

• .htaccess problem
• PHP memory or time limit
• Extension conflict

Solution

1. Rename .htaccess - Test if this is the problem
2. Increase PHP limits - memory_limit, max_execution_time
3. Disable extensions - Via database or FTP
4. Check error logs - In hosting panel

4. Database connection error

Symptom

Cannot connect to the database.

Cause

• Wrong credentials in configuration.php
• MySQL server offline
• Database user permissions

Solution

1. Check configuration.php - $user, $password, $db, $host
2. Test via phpMyAdmin - Does login work?
3. Recreate database user - In cPanel/Plesk
4. Contact hosting - If server offline

5. 404 - Component not found

Symptom

Component pages give 404 error.

Cause

• Component not installed
• URL rewriting problem
• Menu item missing

Solution

1. Install component - Via Extensions > Manage
2. Check .htaccess - Should contain Joomla rewrite rules
3. Create menu item - Link to component
4. Reset SEF URLs - In Global Configuration

6. You are not authorised to view this resource

Symptom

Access denied to page or function.

Cause

• Wrong user group
• ACL settings
• Session expired

Solution

1. Check user permissions - Users > Manage
2. Check ACL - In component options
3. Log in again - Session may have expired
4. Reset password - If account blocked

7. Template not found

Symptom

Template does not load or error about missing template.

Cause

• Template deleted
• Template folder renamed
• Configuration points to wrong template

Solution

1. Check Extensions > Templates - Is template present?
2. Set different template active - As default
3. Reinstall template - Download again
4. Check templateDetails.xml - Must be correct

8. Maximum execution time exceeded

Symptom

Script timeout during extension installation or large operations.

Cause

• PHP max_execution_time too low
• Slow database queries
• Processing large files

Solution

1. Increase in php.ini - max_execution_time = 300
2. Via .htaccess - php_value max_execution_time 300
3. Split large imports - Into smaller parts
4. Install via FTP - Instead of web installer

9. Memory exhausted

Symptom

PHP memory limit reached.

Cause

• Heavy extension
• Processing large images
• Insufficient allocated memory

Solution

1. Increase in php.ini - memory_limit = 256M
2. Via .htaccess - php_value memory_limit 256M
3. Deactivate heavy extensions - Via database
4. Optimize images - Before upload

10. Extension conflict errors

Symptom

Site crashes after extension installation or update.

Cause

• Incompatible extension
• Conflict with other extensions
• Outdated extension

Solution

1. Rename extension folder - Via FTP
2. Check extension version - Matches Joomla version?
3. Update or remove - The conflicting extension
4. Contact extension developer - For support

General tips

• Make regular backups
• Keep Joomla up to date
• Test extensions on staging
• Use reliable extensions

Related articles

• Joomla hosting - Best Joomla hosting
• HTTP 500 error explained - What does this error mean?
• Joomla hub - Everything about Joomla

Frequently Asked Questions

How long does it take to implement this?

Implementation time varies per situation. Simple configurations can be done within an hour, more complex setups may take several hours to a day.

What are the costs?

Costs depend on your hosting provider and package. Many basic features are included for free, advanced features may incur additional costs.

Do I need technical knowledge?

You need little technical knowledge for the basics. Most hosting providers offer extensive documentation and support to help you.