Laravel >= 5.4
php artisan cache:clear chmod -R 777 storage/ composer dump-autoload
Laravel < 5.4
php artisan cache:clear chmod -R 777 app/storage composer dump-autoload
Laravel >= 5.4
php artisan cache:clear chmod -R 777 storage/ composer dump-autoload
Laravel < 5.4
php artisan cache:clear chmod -R 777 app/storage composer dump-autoload
To fix this error you should use this command :
chmod 777 storage/framework/sessions/