Joomla is a powerful and flexible content management system used by millions of websites worldwide. Like any CMS, you may encounter problems. In this article, we cover the 15 most common Joomla problems and provide practical solutions to fix them yourself.

1. White Screen of Death

One of the most frustrating Joomla problems is a blank white page without any error message.

Causes

  • PHP memory limit reached
  • Error in an extension or template
  • Corrupt .htaccess file
  • PHP syntax error

Solution

Step 1: Enable error reporting

Edit configuration.php in your Joomla root:

public $error_reporting = 'maximum';
public $debug = 1;

Step 2: Increase PHP memory

Add to .htaccess:

php_value memory_limit 256M

Step 3: Disable extensions via database

If you can't access the backend, open phpMyAdmin and execute:

UPDATE jos_extensions SET enabled = 0 WHERE type = 'plugin';

Replace jos_ with your own table prefix.

2. Error 500 - Internal Server Error

The generic 500 error can have multiple causes.

Causes

  • Incorrect file permissions
  • Corrupt .htaccess
  • PHP version incompatibility
  • Server configuration problem

Solution

Check .htaccess:

  1. Rename .htaccess to .htaccess_backup
  2. Test the website
  3. Working? Create a new clean .htaccess via Joomla backend

Fix file permissions:

  • Folders: 755
  • Files: 644
  • configuration.php: 444
find /path/to/joomla -type d -exec chmod 755 {} \;
find /path/to/joomla -type f -exec chmod 644 {} \;

3. Cannot login to administrator

You can no longer log in to /administrator.

Causes

  • Wrong password
  • Corrupt session data
  • Blocked by security extension
  • Database problem

Solution

Reset password via database:

  1. Open phpMyAdmin
  2. Go to table jos_users
  3. Find your admin user
  4. Change the password field to:
$2y$10$DpfpYjADpdjXMQCdE4mO9.AwxDJkzQPNxZQvMRSRVDvHZL2rZ6kPi

This is the hashed password for "secret" - change it immediately after logging in!

Clear sessions:

TRUNCATE TABLE jos_session;

4. Website is extremely slow

A slow Joomla website frustrates visitors and hurts your SEO.

Causes

  • Too many or heavy extensions
  • No caching enabled
  • Unoptimized images
  • Slow database queries

Solution

Enable cache:

  1. Go to System → Global Configuration → System
  2. Set Cache to "Conservative caching"
  3. Cache Handler: File

Plugin cache:

  1. Extensions → Plugins
  2. Search "System - Page Cache"
  3. Enable this plugin

Optimize database:

OPTIMIZE TABLE jos_content, jos_categories, jos_assets;

5. Image upload fails

You cannot upload images via the Media Manager.

Causes

  • Upload limit too low
  • Wrong folder permissions on /images
  • File type not allowed
  • PHP configuration

Solution

Increase PHP limits:

Add to .htaccess:

php_value upload_max_filesize 64M
php_value post_max_size 64M
php_value max_execution_time 300

Check folder permissions:

chmod 755 /path/to/joomla/images
chown -R www-data:www-data /path/to/joomla/images

Allowed file types: Go to System → Global Configuration → Media and check the "Legal Extensions".

6. Update failed or stuck

The Joomla update stops halfway or gives an error message.

Causes

  • Insufficient server memory
  • Timeout during download
  • File permissions problem
  • Incompatible extensions

Solution

Manual update:

  1. Download the update package from joomla.org
  2. Unzip the ZIP file
  3. Upload all files via FTP (overwrite existing)
  4. Go to /administrator/components/com_joomlaupdate/restore.php
  5. Follow the wizard

After the update:

  1. Clear all cache
  2. Check extensions for updates
  3. Test the website thoroughly

7. Menu items don't work or give 404

Pages give a 404 error even though they exist.

Causes

  • SEF URLs problem
  • Wrong .htaccess configuration
  • Menu item not published
  • Cache problem

Solution

Check SEF URLs:

  1. System → Global Configuration → Site
  2. Set "Search Engine Friendly URLs" to Yes
  3. Set "Use URL Rewriting" to Yes
  4. Rename htaccess.txt to .htaccess

Clear cache:

  1. System → Clear Cache
  2. Select all and delete

8. Database connection error

"Error connecting to the database" error message.

Causes

  • Wrong database credentials
  • Database server offline
  • Corrupt database
  • Too many connections

Solution

Check credentials in configuration.php:

public $host = 'localhost';
public $user = 'your_db_user';
public $password = 'your_password';
public $db = 'your_database';
public $dbprefix = 'jos_';

Repair database: Via phpMyAdmin: select all tables → click "Repair table"

9. Extension installation fails

You cannot install new extensions.

Causes

  • tmp folder not writable
  • Upload limit too small
  • Extension incompatible
  • Corrupt installation package

Solution

Check tmp folder:

chmod 755 /path/to/joomla/tmp
chmod 755 /path/to/joomla/administrator/tmp

Alternative installation:

  1. Unzip the extension locally
  2. Upload to /tmp folder via FTP
  3. Install via "Install from Folder"

10. Template not displayed correctly

Your template looks wrong or CSS doesn't load.

Causes

  • Cache problem
  • Conflicting CSS
  • Template override problem
  • CDN or browser cache

Solution

Clear browser cache: Use Ctrl+Shift+R (hard refresh)

Clear Joomla cache:

  1. System → Clear Cache - clear all
  2. System → Purge Expired Cache

Reset template overrides: Check /templates/your_template/html/ for old overrides that might conflict.

11. Email sending doesn't work

Joomla doesn't send emails (contact form, registration, etc.)

Causes

  • Wrong mail settings
  • Server blocks outgoing mail
  • SPF/DKIM not correct
  • SMTP authentication problem

Solution

Configure SMTP:

  1. System → Global Configuration → Server
  2. Mailer: SMTP
  3. Fill in:
    • SMTP Host: mail.yourdomain.com
    • SMTP Port: 587
    • SMTP Security: STARTTLS
    • SMTP Authentication: Yes
    • SMTP Username: your full email address
    • SMTP Password: your email password

Test: Go to System → Global Configuration and click "Send Test Mail"

12. "The file Cache Storage is not supported on this platform"

Error message about cache storage.

Causes

  • tmp folder not writable
  • Wrong cache configuration
  • Server permission problem

Solution

Change cache handler:

  1. Edit configuration.php
  2. Change: public $cache_handler = 'file';
  3. Check: public $tmp_path = '/full/path/to/joomla/tmp';

Permissions:

chmod 755 /path/to/joomla/cache
chmod 755 /path/to/joomla/administrator/cache

13. "JFolder::create: Could not create directory"

Joomla cannot create folders.

Causes

  • Wrong file permissions
  • open_basedir restriction
  • Wrong owner

Solution

Correct owner:

chown -R www-data:www-data /path/to/joomla

Permissions:

find /path/to/joomla -type d -exec chmod 755 {} \;

Enable FTP Layer (emergency solution): In configuration.php:

public $ftp_enable = 1;
public $ftp_user = 'ftp_username';
public $ftp_pass = 'ftp_password';

14. SSL/HTTPS redirect loop

Infinite redirect loop after SSL activation.

Causes

  • Double redirect rules
  • Force SSL in Joomla + .htaccess
  • Proxy/CDN configuration

Solution

Choose one method:

Via Joomla (recommended):

  1. System → Global Configuration → Server
  2. Force HTTPS: Entire Site
  3. Remove HTTPS redirects from .htaccess

Or via .htaccess (remove Joomla setting):

RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

15. "You are not authorised to view this resource"

Access denied error message.

Causes

  • Wrong ACL (Access Control List) settings
  • User not in correct group
  • Menu item access level wrong
  • Super User rights lost

Solution

Restore Super User via database:

-- Find your user ID
SELECT id, username FROM jos_users WHERE username = 'admin';

-- Add to Super Users group (group 8)
INSERT INTO jos_user_usergroup_map (user_id, group_id) VALUES (YOUR_USER_ID, 8);

Check access levels:

  1. Users → Access Levels
  2. Check which groups have access
  3. Content → Articles - check the Access column

Preventive maintenance

Prevent problems through regular maintenance:

  1. Weekly: Clear cache, check updates
  2. Monthly: Optimize database, remove unused extensions
  3. Always: Make backup before changes

Making backups

Install Akeeba Backup:

  1. Download from extensions.joomla.org
  2. Install via Extensions → Install
  3. Make regular backups
  4. Store backups externally

Need help?

Can't figure it out? Our support team is here for you! Submit a ticket through the customer portal and we'll usually help you within a few hours.