“Aapt”任务无法实例化

Question

我正在使用Xamarin和Visual Studio使用Xamarin.Forms创建一个应用程序;在构建我的解决方案之后，它向我显示了一些关于AndroidManifest.xml和错误的消息。

讯息：

1. Could not find schema information for the element 'application'
2. Could not find schema information for the element 'manifest'
3. Could not find schema information for the element 'uses-sdk'

错误：

1. The "Aapt" task could not be instantiated from "C:\Program Files (x86) \MSBuild \Xamarin\Android \Xamarin.Android.Build.Tasks.dll".
2. The "Aapt" task has been declared or used incorrectly, or failed during construction. Check the spelling of the task name and the assembly name.

我使用VS2015，请帮我解决这个问题。