How to open new window using Asp.net ?

Protected Sub lbnDemo_Click(ByVal sender As Object, ByVal e As System.EventArgs)

        Try

        

            ScriptManager.RegisterStartupScript(Me.Page, Me.GetType(), "window", "ViewInternalID();", True)

        Catch ex As Exception

            SetUserMessage(ex.Message, MessageType.ErrorMessage)

            ErrorSignal.FromCurrentContext.Raise(ex)

        End Try

    End Sub

<script type="text/javascript">

 function ViewInternalID()

  {

  window.open(" Default .aspx",'_blank','width=800px,height=500px,scrollbars=yes, status=no, resizable');

   }

 

   

    </script>