ASP.NET "Could not Load Type" just on Server

I have a ASP.Net 3.5 host. I just opened a new, C# Web project in visual studio 2010. I changed customerror to None and delete authentication mode line and select None in server control panel. Project works on local machine and says Hello World when I build and deploy in to server via FTP, I get an error it says Could not Load Type '_Default' <%@ page language="C#" autoeventwireup="true" CodeFile="Default.aspx.cs" inherits="WebApplication._Default" %>

my namespace is 开发者_开发知识库WebApplication and in class name is _Default Default.aspx.cs,

It works when I start in ISS, but It cannot start on server.

The error might be coming because you are trying to publish two sites on a single server ftp. It can be solved if you upload it on a sub-domain.

This error is always related to a bad deployment. Either that code file wasn't published or your missing an assembly somewhere.

Also, you might want to check to verify the server does indeed have all of the 3.5 stuff loaded on it.