win2008 r2 iis7.5 zend安装问题求助！

环境：win2008 r2 php5.2.17+mysql+zend+iis7.5+xcache.

用phpinfo查看信息如下：这个提示应该是标示已经安装成功了吧。

This program makes use of the Zend Scripting Language Engine:

Zend Engine v2.2.0, Copyright (c) 1998-2010 Zend Technologies

    with XCache v1.3.2, Copyright (c) 2005-2011, by mOo

    with Zend Extension Manager v1.2.0, Copyright (c) 2003-2007, by Zend Technologies

    with Zend Optimizer v3.3.3, Copyright (c) 1998-2007, by Zend Technologies

但是打开网站提示:
Zend Optimizer not installed

This file was encoded by the Zend Guard. In order to run it, please install the Zend Optimizer (available without charge), version 3.0.0 or later.

运行的空间不支持zend？

自己的服务器，重新装了下ZEND竟然可以了。也不知道原因在那