When and where does a UserControl compile
<p>I have a page, Default.aspx, and a UserControl, HelloControl.ascx.  In the page, I dynamically instantiate the control as follows:</p>

<pre><code>protected void Page_Load(object sender, EventArgs e)
{
    HelloControl c = Page.LoadControl(typeof (HelloControl), null) as HelloControl;
    c.Greet();
}
</code></pre>

<p>This works fine, and the user control writes "Hello from a control" to the response.  I have no @Register directive in Default.aspx, but when I try a similar dynamic control creation on a client's machine, I get an error that the "Type or Namespace  does not exist".  </p>

<p>I have even gotten feedback, on forums, from MS, that I need the @Register directive, but I obviously don't.  Can anyone help me out with info on how and when the user control is compiled if no @Register directive references it?</p>

<p>EDIT:  I have tried a different direction of investigation, losing my initial call to LoadControl, and I still can't reproduce the problem.  The following code also works fine on my dev machine, without any @Register directive.</p>

<pre><code>protected void Page_Load(object sender, EventArgs e)
{
    HelloControl c = new HelloControl();
    Response.Write(c.Greet());
}
</code></pre>
