无法将LINQ添加到ASP。网网页

I've got a simple ASP.NET website, but I can't get it to work. The server is running IIS 7.5 with .NET 4.0 installed, and I've got complete access, and I'm using VS2010 to generate an ASP.NET 4 website. But VS automatically generates code-behind files with I've got a simple ASP.NET website, but I can't