Cryptic error message

Can you make any sense of this error?

Exception
Object reference not set to an instance of an object.
at ae.b()
at ae.a(b3 A_0)
at Aspose.Excel.Worksheets.e(b3 A_0)
at Aspose.Excel.Worksheets.f(b3 A_0)
at Aspose.Excel.Worksheets.d(b3 A_0)
at Aspose.Excel.Worksheets.a(String A_0, SaveType A_1, FileFormatType A_2, HttpResponse A_3)

Sorry for the problem.

In what situation this exception occurs? And which version are you using? Please elaborate your problem so I can investigate it.

Version 1.8.0.0

We are not doing anything complicated. We do this:

1) Create some styles in the Excel object
2) For every DataTable in a DataSet
2a) create a new work sheet
2b) call ImportDataTable
2c) Apply a style on the header row
2d) Apply styles on the columns based on some text specified in the ExtendedProperties of each DataColumn
2e) Call AutoFit on every column in the worksheet.
3) Save, using SaveType.OpenInExcel

I cant give you specific data because it has only happened a few times and I cannot reproduce it.

In your source code, can you determine what objects are being used and what objects could potentially be null?

Sorry, I have no ideas about your problem.

Please download hotfix 1.8.4 and have a try. I have fixed several bugs which may cause null-reference problem.