Private Sub ButtonStampa_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ButtonStampa.Click
    InizializzaStampante()
    Stampa()
    ChiudiStampante()
  End Sub


  Public Sub InizializzaStampante()
    '<<<step1>>>--Start
    'Use a Logical Device Name which has been set on the SetupPOS.
    Dim strLogicalName As String
    Dim deviceInfo As DeviceInfo
    Dim posExplorer As PosExplorer

    strLogicalName = "PosPrinter"

    'Create PosExplorer
    posExplorer = New PosExplorer

    m_Printer = Nothing

    Try

      deviceInfo = posExplorer.GetDevice(DeviceType.PosPrinter, strLogicalName)
      m_Printer = posExplorer.CreateInstance(deviceInfo)

    Catch ex As Exception
      Return
    End Try

    Try

      'Open the device
      m_Printer.Open()

      'Get the exclusive control right for the opened device.
      'Then the device is disable from other application.
      m_Printer.Claim(1000)

      'Enable the device.
      m_Printer.DeviceEnabled = True

    Catch ex As PosControlException
      m_Printer.Release()
    End Try
  End Sub

  Public Sub Stampa()
    Try
      'As using the PrintNormal method, send strings to a printer, and print it
      '[vbCrLf] is the standard code for starting a new line.
      m_Printer.PrintNormal(PrinterStation.Receipt, "Hello OPOS for .Net" + vbCrLf)

    Catch ex As PosControlException

    End Try
    '<<<step2>>> End
  End Sub

  Public Sub ChiudiStampante()
    If m_Printer Is Nothing Then
      Return
    End If

    Try
      'Cancel the device
      If m_Printer.DeviceEnabled Then
        m_Printer.DeviceEnabled = False
      End If

      'Release the device exclusive control right.
      m_Printer.Release()


    Catch ex As Exception

    Finally
      'Finish using the device.
      m_Printer.Close()

    End Try
  End Sub

================== Exception =====================
Microsoft.PointOfService.PosControlException
ErrorCode : Failure (111)
ErrorCodeExtended : 0
Message : It is not initialized.
Target : System.String CheckHealth(Microsoft.PointOfService.HealthCheckLevel)
## StackTrace ##
  at jp.co.epson.upos.pntr.CommonPrinterService.CheckHealth(HealthCheckLevel level)
  at CheckHealthTest.MainForm.ExecuteCheckHealth(DeviceInfo objInfo)
  at CheckHealthTest.MainForm.btnCheckHealth_Click(Object sender, EventArgs e)