' ContactUs.aspx
<asp:Label ID="lblMessageSend" runat="server" Text="Your message has been send succesfully, Thank You!"></asp:Label>

' ContactUs.aspx.vb
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    lblMessageSend.Visible = False
    hplContinue.Visible = "false"
End Sub

' ContactUs.aspx.designer.vb
Protected WithEvents lblMessageSend As Global.System.Web.UI.WebControls.Label

'ERROR:
'lblMessageSend' is not declared. It may be inaccessible due to its protection level.