I am executing the following code. Sometimes it works, sometimes it doesn't. I can't figure out what is causing these transient errors. The code is erroring out on this line, so I can't trap deeper into the workings to see just why.

UltraGridExcelExporter1.Export(UltraGrid1, myWorkbook, 0, 0) 

With this error:

Error Code -3; Error in Workbook_Export(): System.IndexOutOfRangeException: Index was outside the bounds of the array.

   at Excel_Exporter.Form1.UltraGridExcelExporter1_CellExporting(Object sender, CellExportingEventArgs e) in Z:\Visual Studio Projects\Excel_Exporter_Winforms\Excel_Exporter_Winforms\Form1.vb:line 275

   at Infragistics.Win.UltraWinGrid.ExcelExport.UltraGridExcelExporter.OnCellExporting(CellExportingEventArgs e)

   at Infragistics.Win.UltraWinGrid.ExcelExport.UltraGridExcelExporter.ExportRowValuesCells(UltraGridExporterHelper exportHelper, UltraGridRow row)

   at Infragistics.Win.UltraWinGrid.ExcelExport.UltraGridExcelExporter.WriteSingleRow(UltraGridExporterHelper exportHelper, UltraGridRow row)

   at Infragistics.Win.UltraWinGrid.ExcelExport.UltraGridExcelExporter.ProcessSingleRow(UltraGridExporterHelper exportHelper, UltraGridRow row)

   at Infragistics.Win.UltraWinGrid.RowsCollection.InternalTraverseRowsHelper(IUltraGridExporter exporter)

   at Infragistics.Win.UltraWinGrid.UltraGrid.Export(IUltraGridExporter exporter)

   at Infragistics.Win.UltraWinGrid.ExcelExport.UltraGridExcelExporter.Export(UltraGrid grid, Workbook workbook, Int32 startRow, Int32 startColumn)

   at Excel_Exporter.Form1.WorkBook_Export(String File_Path) in Z:\Visual Studio Projects\Excel_Exporter_Winforms\Excel_Exporter_Winforms\Form1.vb:line 168

The code:

Private Sub WorkBook_Export(ByVal File_Path As String)
Try
Dim myWorkbook As New Infragistics.Documents.Excel.Workbook
myWorkbook.Worksheets.Add("sheet1")

If protect_sheet = "Prot" Then
''''myWorkbook.Protect(CBool(True), CBool(False))
''''myWorkbook.Worksheets("sheet1").Columns(1).CellFormat.Locked = Infragistics.Documents.Excel.ExcelDefaultableBoolean.True
''''myWorkbook.Protect(False, True,)

'''''''''If Worksheet_PW <> "" Then
''''''''' myWorkbook.Protect(Worksheet_PW, False, False)
''''''''' 'myWorkbook.SetFileWriteProtectionPassword(Worksheet_PW)
'''''''''Else
''''''''' myWorkbook.Protect(False, False)
'''''''''End If
End If
UltraGridExcelExporter1.Export(UltraGrid1, myWorkbook, 0, 0)
'Save the Workbook to a file.
myWorkbook.Save(File_Path)

UltraGridExcelExporter1.Dispose()
Catch ex As Exception
' MsgBox(ex.ToString)
error_code = -3
Error_Flag = True
Error_Msg = "Error Code -3; Error in Workbook_Export(): " & ex.ToString
Send_Error_Email()
End Try
End Sub