I want to use Server.MapPath() method im order to map a virtual directory I created to its physical path.
The thing is that the .net environment doesn\'t recognize S
If you have a web application, you should automatically have a reference to System.Web.dll, and you should have access to the System.Web.HttpContext class. Check that you haven't accidentally removed the reference. You would need a using System.Web; statement to access the HttpContext class without specifying the complete namespace.
If you don't have a web application you would have to add a referece to System.Web.dll to get access to the HttpContext class, but that would not help you a bit. As you are not in a web application, there is no HTTP context and there is no web root folder, so you can not use the MapPath method.