Error: The name 'Message' Does not Exist in the Current Context

I copied the following code from msdn which gives me an error "The name 'Message' Does not Exist in the Current Context"
Am I missing something for this code?
<script runat="server"> void Check_Clicked(Object sender, EventArgs e) { Message.Text = "Selected Item(s):<br /><br />"; for (int i=0; i<checkboxlist1.Items.Count; i++) { if (checkboxlist1.Items[i].Selected) { Message.Text += checkboxlist1.Items[i].Text + "<br />"; } } } </script>
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