在本地测试已经正常可用了。但到了虚拟主机上出现找不到类！文件一致！求助求指教！

Fatal error: Class 'PHPExcel' not found in /www/web/ningcheng/public_html/Lib/Action/Admin/OrderAction.class.php on line 14
:(
Class 'PHPExcel' not found
错误位置
FILE: /www/web/ningcheng/public_html/Lib/Action/Admin/OrderAction.class.php 　LINE: 14
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