ASpose Cells : This is not a structured storage file

Hi we are using your product for our app.
When I am reading from .xls file throws Exception: This is not a structured storage file.

LoadOptions options = new LoadOptions(LoadFormat.Excel97To2003);
var excleFile = new FileStream(path, FileMode.Open);
Workbook workbook = new Workbook(excleFile, options )

Please. Could you help me?
Thanks in Advance


Thanks for the sample code and details.

Please attach your template XLS file (you may zip prior attaching), we will check it soon. (5.3 KB)


Thanks for the templte file.

I tested your scenario/ case a bit using your template file with Aspose.Cells for .NET v19.1 (please try it). I found no issue or exception using your sample code. It works fine. Also, I found your so called XLS file is actually an XLSX file, so you may also try to change the line of your code:

LoadOptions options = new LoadOptions(LoadFormat.Excel97To2003);


LoadOptions options = new LoadOptions(LoadFormat.Auto);

If you still find the issue with v19.1, do let us know with details and sample code, we will check it soon.

@Amjad_Sahi Thanks a lot.

Could you say How can I check actual file type?

Thanks in advance

I’ve found it thanks a lot.

Best Regards
Grigor Vardanyan


Good to know that you have sorted it out now. You may check the following document on how to detect file format for your further reference:

Feel free to contact us any time if you need further help or have some other issue or queries, we will be happy to assist you soon.

Thanks a lot for quick response