FileUploadField Visible property in code behind not working

[xtremexploit]

aspx

  <ext:FileUploadField ID="cerSubirFileUploadField" runat="server" Width="300" Icon="Attach"
                                    Text=".cer" />


   <ext:Button ID="SaveButton" runat="server" Text="Instalar">
                                    <DirectEvents>
                                        <Click OnEvent="SubirCertificadoClick">
                                        </Click>
                                    </DirectEvents>
                                </ext:Button>

protected void SubirCertificadoClick(object sender, DirectEventArgs e)
{
cerSubirFileUploadField.Visible = false;
}

[Vladimir]

You have to use Hidden property (Visible must be used to prevent widget rendering only)