Fatal error: Uncaught Error: Class "PHPExcel_CachedObjectStorage_CacheBase" not found in D:\xampp\htdocs\PHPExcel\CachedObjectStorage\Igbinary.php:28 Stack trace: #0 {main} thrown in D:\xampp\htdocs\PHPExcel\CachedObjectStorage\Igbinary.php on line 28