[asp.net 3] problema lettura db

[Titusn]

Sono nuovo in ambito asp.net 3 eseguendo la queri qui sotto mi restituisce il messagge di errore

"Errore - No data exists for the row/column. "

Qualcuno puo darmi una mano ?

tnx

   Me.errore.Visible = False
        Dim Stringa_connessione As String = "Provider=SQLOLEDB.1;Password=user2009db;Persist Security Info=True;User ID=userdb;Initial Catalog=Repas;Data Source=172.20.1.47"
        Dim conn As New OleDb.OleDbConnection
        conn.ConnectionString = Stringa_connessione
        conn.Open()

        Try

            Dim Sql As String = "SELECT * FROM OPERATORI WHERE vch_user = '" & Me.vch_username.Text & "' AND vch_pass = '" & Me.vch_pass.Text & "'"
            Dim cmd = New OleDbCommand(Sql, conn)
            Dim rs As OleDbDataReader

            rs = cmd.ExecuteReader()

            If rs.HasRows Then

                If rs.Item("bool_amministratore") Then

                    Response.Write("<script> " & vbCrLf & " document.location.href='webform2.aspx';" & vbCrLf & " </script>")

                Else

                    Response.Write("<script> " & vbCrLf & " document.location.href='Default.aspx';" & vbCrLf & " </script>")

                End If

            Else

                Me.errore.Text = "Utente Non Riconosciuto"
                Me.errore.Style.Add("color", "red")
                Me.errore.Visible = True

            End If

                rs.Close()


        Catch ex As Exception

            Me.errore.Text = "Errore  -  " & ex.Message
            Me.errore.Style.Add("color", "red")
            Me.errore.Visible = True


        End Try

        conn.Close()