Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button3.Click
        Dim sw As New System.IO.StreamWriter(".\Fake\serial.txt", False, _
        System.Text.Encoding.Default)
        If MaskedTextBox1.Text <> "" Then
            Using sw
                sw.Write(MaskedTextBox1.Text)
            End Using
        End If
    End Sub

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