This assembly may have been downloaded from the Web. ......

错误消息例如：

Error 6 Could not load the assembly file:///D:meProjectsDLLNewtonsoft.JsonPortable40Newtonsoft.Json.dll.

This assembly may have been downloaded from the Web. If an assembly has been downloaded from the Web, it is flagged by Windows as being a Web file, even if it resides on the local computer. This may prevent it from being used in your project. You can change this designation by changing the file properties. Only unblock assemblies that you trust. See http://go.microsoft.com/fwlink/?LinkId=179545 for more information. Weishi

解决方法：

在DLL文件属性里点击 “解除锁定”按钮！！