问题：

Error:Failed to open zip file.
Gradle's dependency cache may be corrupt (this sometimes occurs after a network connection timeout.)
Re-download dependencies and sync project (requires network)
Re-download dependencies and sync project (requires network)

Gradle Projects needs to be imported

解决：

1.build tools, platform tools版本要一致（SDK Manager中查看）；

2.发生如上问题，删除C:\User\account.\.gradle, .android, .androidstudio, .intelidea…目录，然后重启AS, IDEA;

3.如果IDEA目录中缺少gradle文件夹，则拷贝一个过来

Android Studio 出现 Gradle's dependency cache may be corrupt 错误分析 - u011277123的博客 - 博客频道 - CSDN.NET
http://blog.csdn.net/u011277123/article/details/52096864

Android Studio 出现 Gradle's dependency cache may be corrupt 错误分析 - 银灵子 - 博客频道 - CSDN.NET
http://blog.csdn.net/u014231734/article/details/41913775