asp.net MVC 3安装 EFCode失败

工具”菜单下的“Library Package Manager”子菜单下的“Package Manager Console”菜单选项,

如果  Package Manager Console提示错误

请下载安装
http://www.microsoft.com/downloads/zh-cn/details.aspx?FamilyID=863E7D01-FB1B-4D3E-B07D-766A0A2DEF0B
因为我的系统是2008 你根据你的系统下载对应更新文件

安装完成提示重启

在Package Manager Console中输入以下命令安装EFCodeFirst

PM> install-package efcodefirst

PM> install-package efcodefirst
未安装“EntityFramework (≥ 4.1.10331.0)”。正在尝试从源检索依赖项...
完成
You are downloading EntityFramework from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=211010. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device.
已成功安装“EntityFramework 4.1.10331.0”
已成功安装“EFCodeFirst 1.1”
已成功将“EntityFramework 4.1.10331.0”添加到 MvcTest
已成功将“EFCodeFirst 1.1”添加到 MvcTest

PM>

以下网上说过到的步骤 最后我还是没有安装成功

工具”菜单下的“Library Package Manager”子菜单下的“Add Library Package Reference”菜单选项,
点击左边面板中的“online”
在右上角的搜索输入框中输入“EFCode”。在检索结果中，选择EFCodeFirst包，并且点击Install按钮安装包
如果安装时提示（
This package (or one of its dependencies) contains PowerShell scripts and needs to be installed from the Package Manger Console
）
请下载安装
http://www.microsoft.com/downloads/zh-cn/details.aspx?FamilyID=863E7D01-FB1B-4D3E-B07D-766A0A2DEF0B
因为我的系统是2008 你根据你的系统下载对应更新文件

下载安装更新 还是提示以上错误信息

不知道是什么原因

请高手指教