System.Net question

Unity is giving me an error
I am trying to build a project to web player. It builds perfectly to a stand alone however when i build to a web player I get this error. What should i do?

“Assets/ShanScriptsAndShaders/ShanDataBaseScripts/NetworkInfo.cs(3,18): error CS0234: The type or namespace name NetworkInformation' does not exist in the namespace System.Net’. Are you missing an assembly reference?”

I don’t understand what the error is talking about.

any help?

Unity may have decided not to include this into their web player built due to security concerns. You can ty to forcefully include the library by copying and pasting it into an “Assets/Plugins” folder and try compiling again.

You have to choose PC,Mac & StandAlone Platform or others at build settings window,if you want use System.Net dll then you can not choose platform WebPlatform