Botón para buscar archivo

        ' Dim openFileDialog1 As OpenFileDialog = New OpenFileDialog()
        Dim openFileDialog1 As New OpenFileDialog()
        openFileDialog1.Filter = "Acceso Directo (*.txt)|*.txt"
        If openFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
            tb_ruta_conex.Text = openFileDialog1.FileName
        Else
            Exit Sub
        End If