Fixing session_start(): Permission Denied (13) in XAMPP — System Administrator's Guide

What Does This Error Mean?

The error occurs when PHP cannot access the session storage directory (/applications/xampp/xamppfiles/temp/) due to permission issues, incorrect ownership, or configuration errors.

For related session_start permission topics, see Fixing session_start() failed: Permission denied (13), Failed to Read Session Data (read-side), and XAMPP — SELinux/AppArmor restrictions variant.

Common Causes:

1. Incorrect permissions on the session directory (/applications/xampp/xamppfiles/temp/).
2. Wrong ownership (Apache/Nginx cannot write session files).
3. Misconfigured php.ini session path.
4. Session directory missing or corrupt session files.
5. SELinux or security restrictions preventing access (Linux/macOS).

Find the PHP Session Directory

Check PHP Session Path in XAMPP

Run:

php -i | grep "session.save_path"

Expected output:

session.save_path => /applications/xampp/xamppfiles/temp

If the session path is empty, it means PHP is using the system's default temporary folder (/tmp).

Ensure the Session Directory Exists

If the session directory is missing, create it.

sudo mkdir -p /applications/xampp/xamppfiles/temp

Fix Directory Permissions

Grant Read/Write Permissions to the Web Server

Set correct permissions so Apache/Nginx can write session files:

sudo chmod -R 770 /applications/xampp/xamppfiles/temp

Set Correct Ownership

For Apache (default user daemon on macOS XAMPP):

sudo chown -R daemon:daemon /applications/xampp/xamppfiles/temp

For Linux (Ubuntu/Debian/Arch), if running XAMPP manually:

sudo chown -R www-data:www-data /applications/xampp/xamppfiles/temp

Restart XAMPP and test again:

sudo /Applications/XAMPP/xampp restart

Verify php.ini Configuration

If PHP is using the wrong session path, update php.ini.

Locate php.ini in XAMPP

For macOS:

sudo nano /Applications/XAMPP/xamppfiles/etc/php.ini

For Linux:

sudo nano /opt/lampp/etc/php.ini

Update Session Settings

Find and modify:

session.save_handler = files
session.save_path = "/applications/xampp/xamppfiles/temp"
session.gc_maxlifetime = 3600
session.use_strict_mode = 1
session.cookie_secure = 0

If /applications/xampp/xamppfiles/temp is restricted, use /tmp/php_sessions instead.

Restart XAMPP

sudo /Applications/XAMPP/xampp restart

Clear Old or Corrupt Session Files

Corrupt session files can prevent new ones from being created.

sudo rm -rf /applications/xampp/xamppfiles/temp/*

Try running the session script again.

Debug with Error Logs

If the problem persists, check logs.

Check XAMPP Logs

sudo tail -f /Applications/XAMPP/logs/php_error_log

Check Apache Logs

sudo tail -f /Applications/XAMPP/logs/error_log

Summary of Fixes

By following these systematic fixes, you can resolve session_start() permission errors in XAMPP and restore PHP session functionality.