ASP.Net 4.0 Website not working in ASP.Net Classic Application Pool in IIS 7

Hi,

I have a ASP.NET application which contains ASPX pages, but when I set the application pool to ASP.NET v4.0 Classic, I encounter an error stating

HTTP Error 404.2 - Not Found

The page you are requesting cannot be served because of the ISAPI and CGI Restriction list settings on the Web server.

         Detailed Error Information

But the same application works fine for

. ASP.NET v4.0  Integrated Application pool. I'm using IIS7

Cna anyone please share thoughts on this?

Thanks,

Nayana