The type 'System.Object' is defined in an assembly that is not referenced

记录一个错误，报 The type 'System.Object' is defined in an assembly that is not referenced，[System.Runtime]

配置文件加上后仍报错！ 

<system.web>

    <compilation debug="true" targetFramework="4.5">

      <assemblies>

        <add assembly="System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>

      </assemblies>

    </compilation> 

  </system.web>

解决方法：移除Bin System.ValueTyple.dll rebuild成功。