Why is an option or command unavailable ?

选项或命令不可用的原因？

The product provides true application and infrastructure modularity unavailable in other product stacks .

该产品可提供在别的产品线上无法实现的应用和基础模块。

Proxy server is unavailable . Try connecting to proxy xx again ?

proxy服务器无效。尝试重新连接到代理xx吗？

The online recruitment testing system is temporarily unavailable due to scheduled maintenance work .

由于日常系统的维护，目前的招聘测试系统暂时不能使用。

A spokesman for bain was unavailable for comment tuesday .

记者周二无法联系到贝恩资本的发言人置评。