Ocr problem with error

doc.OCR(MODI.MiLANGUAGES.miLANG_ENGLISH, True, True)

Public Class frmOCRextract
    Private extractedText As String = String.Empty
    Private getFileName As String
    Dim openFile As New OpenFileDialog
    'Browsing an image
    Private Sub btnBrowse_Click(sender As Object, e As EventArgs) Handles btnBrowse.Click

        If openFile.ShowDialog = DialogResult.OK Then

            getFileName = openFile.FileName

            Dim targetImage As Image = Image.FromFile(getFileName)
            'Dim targetimage As Image = getFileName

            targetImage = fitInPBox(targetImage)


            pBox.Image = targetImage
        End If
    End Sub
    'This function fit the browsed image in picture box
    Private Function fitInPBox(img As Image) As Image
        Dim ixc As New Bitmap(img, New Size(pBox.Size.Width, pBox.Size.Height))
        Return DirectCast(ixc, Image)
    End Function
    'Extract button working, text is extracted from image
    Private Sub btnExtract_Click(sender As Object, e As EventArgs) Handles btnExtract.Click
        Dim doc As New MODI.Document()
        doc.Create(getFileName)
        doc.OCR(MODI.MiLANGUAGES.miLANG_ENGLISH, True, True)
        Dim img As MODI.Image = DirectCast(doc.Images(0), MODI.Image)
        Dim layout As MODI.Layout = img.Layout

        For i As Integer = 0 To layout.Words.Count - 1
            Dim word As MODI.Word = DirectCast(layout.Words(i), MODI.Word)

            If extractedText.Length > 0 Then
                extractedText += " "
            End If

            extractedText += word.Text
            RichTextBox1.Text = extractedText
        Next


    End Sub
End Class