I have an error : "The Configuration could not be saved." when I'm uploading a file

Configuration.php

<?php
App::uses('AppModel', 'Model');
/**
 * Configuration Model
 *
 */
class Configuration extends AppModel {

/**
 * Display field
 *
 * @var string
 */
	public $displayField = 'profession';

	public $validate = array(
		'userphoto' => array(
			'uploadError' => array(
				'rule' =>'uploadError',
				'message' => 'Your image upload failed',
				//'last' => false, // Stop validation after this rule
				'on' => 'create' // Limit validation to 'create' or 'update' operations
			),
			'mimeType' => array(
				'rule' => array('mimeType', array('image/gif', 'image/png', 'image/jpg', 'image/jpeg')),
				'message' => 'Please only upload images (gif, png, jpg).',
				'on' => 'create'
				),
			'fileSize' => array(
				'rule' => array('fileSize', '<=', '2MB'),
				'message' => 'Your image must be less than 2MB or(2048ko).',
				'on' => 'create'
				),
			'processCoverUpload' => array(
				'rule' => 'processCoverUpload',
				'message' => 'Unable to process cover image upload.',
				'on' => 'create'
				),
			'unique' => array(
				'rule' => 'isUnique',
				'message' => 'This file name is already exist in your folder',
				'on' => 'create'
				),
		),
	
	);
	public function processCoverUpload($check = array()) {
            if (!is_uploaded_file($check['userphoto']['tmp_name'])) {
                return FALSE;
            }
            if (!move_uploaded_file($check['userphoto']['tmp_name'], WWW_ROOT . 'img' . DS . 'uploads' . DS . $check['userphoto']['name'])) {
                return FALSE;
            }
            $this->data[$this->alias]['userphoto'] = 'uploads' . DS . $check['userphoto']['name'];
            return TRUE;
        }

}

ConfigurationsController.php

<?php
App::uses('AppController', 'Controller');
/**
 * Configurations Controller
 *
 * @property Configuration $Configuration
 * @property PaginatorComponent $Paginator
 */
class ConfigurationsController extends AppController {

/**
 * Components
 *
 * @var array
 */
	public $components = array('Paginator');

	function beforeFilter(){
 	parent::beforeFilter();
 	$this->Auth->allow('listConfigurations');
 }

/**
 * edit method
 *
 * @throws NotFoundException
 * @param string $id
 * @return void
 */
	public function edit($id = null) {
		if (!$this->Configuration->exists($id)) {
			throw new NotFoundException(__('Invalid configuration'));
		}
		if ($this->request->is('post') || $this->request->is('put')) {
			

		if(isset($this->request->data['Configuration']['userphoto'])){
		                $file = $this->request->data['Configuration']['userphoto'];
		                if ($file['error'] === UPLOAD_ERR_OK) {
		                    $filename = $file['name'];
		                    if (move_uploaded_file($file['tmp_name'],  WWW_ROOT . 'img' . DS . 'uploads' . DS .$file['name'])) {
		                      $this->request->data['Configuration']['userphoto'] = $filename;
		                    }
		                }
		                if ($this->Configuration->save($file)) {
							$this->Session->setFlash(__('The Configuration has been saved.'));
							return $this->redirect(array('action' => 'index'));
						} else {
							$this->Session->setFlash(__('The Configuration could not be saved. Please, try again.'));
						}

		            }
		} else {
			$options = array('conditions' => array('Configuration.' . $this->Configuration->primaryKey => $id));
			$this->request->data = $this->Configuration->find('first', $options);
		}
		//render a view.

	}


}// end configuration

edit.ctp

<div class="configurations form">
<?php echo $this->Form->create('Configuration', array('type' => 'file')); ?>
	<fieldset>
		<legend><?php echo __('Edit Configuration'); ?></legend>
	<?php
		echo $this->Form->input('id');
		echo $this->Form->input('username');
		echo $this->Form->input('profession');
		echo $this->Form->input('description', array('type' => 'textarea','label' => 'Content of this Article', 'rows' => '10', 'cols' => '120'));
		echo $this->Form->input('userphoto', array('type' => 'file'));
		echo $this->Form->input('tel_mobile');
		echo $this->Form->input('address');
	?>
	</fieldset>
<?php echo $this->Form->end(__('Submit')); ?>
</div>
<div class="actions">
	<h3><?php echo __('Actions'); ?></h3>
	<ul>

		<li><?php echo $this->Form->postLink(__('Delete'), array('action' => 'delete', $this->Form->value('Configuration.id')), null, __('Are you sure you want to delete # %s?', $this->Form->value('Configuration.id'))); ?></li>
		<li><?php echo $this->Html->link(__('List Configurations'), array('action' => 'index')); ?></li>
	</ul>
</div>