I created a web form called JarControl.aspx and then tried to convert it to become a user control, JarControl.ascx

As you can see in my pic, I have changed all the extensions to ascx
And I have changed the code behind file to inherit from
System.Web.UI.UserControl.
Code:
CODE
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class JarControl : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{
}
}
It still gives me that annoying red underline (see pic) and Validation errors such as:
Validation (ASP.Net): Attribute 'Control' is not a valid attribute of element 'Page'.
I've tried saving and building the project a few times - doesn't get rid of it.