Kohana Cache "Permission denied" fix (Windows 7)

<?php defined('SYSPATH') or die('No direct script access.');

class Cache_File extends Kohana_Cache_File {

    /**
     * Retrieve a cached value entry by id.
     *
     *     // Retrieve cache entry from file group
     *     $data = Cache::instance('file')->get('foo');
     *
     *     // Retrieve cache entry from file group and return 'bar' if miss
     *     $data = Cache::instance('file')->get('foo', 'bar');
     *
     * @param   string   id of cache to entry
     * @param   string   default value to return if cache miss
     * @return  mixed
     * @throws  Cache_Exception
     */
    public function get($id, $default = NULL)
    {
        $filename = Cache_File::filename($this->_sanitize_id($id));
        $directory = $this->_resolve_directory($filename);

        // Wrap operations in try/catch to handle notices
        try
        {
            // Open file
            $file = new SplFileInfo($directory.$filename);

            // If file does not exist
            if ( ! $file->isFile())
            {
                // Return default value
                return $default;
            }
            else
            {
                // Open the file and parse data
                $created  = $file->getMTime();
                $data     = $file->openFile();
                $lifetime = $data->fgets();

                // If we're at the EOF at this point, corrupted!
                if ($data->eof())
                {
                    throw new Cache_Exception(__METHOD__.' corrupted cache file!');
                }

                $cache = '';

                while ($data->eof() === FALSE)
                {
                    $cache .= $data->fgets();
                }

                // Test the expiry
                if (($created + (int) $lifetime) < time())
                {
                    if (Kohana::$is_windows === TRUE)
                    {
                        // $data is a SplFileObject with a lock on the file
                        // Unsetting it appears to release the lock, allowing
                        // the file to be deleted
                        unset($data);
                    }
                    // Delete the file
                    $this->_delete_file($file, NULL, TRUE);
                    return $default;
                }
                else
                {
                    return unserialize($cache);
                }
            }

        }
        catch (ErrorException $e)
        {
            // Handle ErrorException caused by failed unserialization
            if ($e->getCode() === E_NOTICE)
            {
                throw new Cache_Exception(__METHOD__.' failed to unserialize cached object with message : '.$e->getMessage());
            }

            // Otherwise throw the exception
            throw $e;
        }
    }

}