Find Control on MasterPage returns nulll
<p>Im trying to access a ModalPopupExtender control and it allways is returning null or object set not set to an intance of an object. I've tried master.Page.FindControl("") and master.FindControl("") and im still not getting the result</p>

<pre><code>MasterPage master = Page.Master as MasterPage;
AjaxControlToolkit.ModalPopupExtender popup = master.Page.FindControl("ModalPopupExtender2") as AjaxControlToolkit.ModalPopupExtender;
</code></pre>

<p>Updated: Cannot change the text of my labels in master page</p>

<pre><code>MasterPage master = Page.Master;
AjaxControlToolkit.ModalPopupExtender popup1 = master.FindControl("ModalPopupExtender1") as AjaxControlToolkit.ModalPopupExtender;
Label lblMessage = master.FindControl("lblMessage") as Label;
lblMessage.Text = msg;
Literal ltrlMessage = master.FindControl("ltrlMessage") as Literal;
ltrlMessage.Text = msg;

Label MessageStatus = master.FindControl("lblMessageStatus") as Label;
MessageStatus.Text = msgStatus;        
popup1.Show();
</code></pre>
