As I requested you earlier, please do not involve Aspose.Cells component, please just read / save the XLSM file using FileStream and Response object. I suspect, there is some issue opening the XLSM file on the fly by Response object in your browser type on your end. You should get the similar issue when using your own .NET code replaced by Aspose.Cells code, e.g.workbook.Save(HttpContext.Current.Response, fileName, ContentDisposition.Attachment, new OoxmlSaveOptions(SaveFormat.Xlsm));
Or confirm your issue by replacing the following lines of code in your project with below code instead.
workbook.Save(HttpContext.Current.Response, fileName, ContentDisposition.Attachment, new OoxmlSaveOptions(SaveFormat.Xlsm));
/Send workbook to response/
OoxmlSaveOptions xSaveOptions = new OoxmlSaveOptions(SaveFormat.Xlsm);
MemoryStream tempStream = new MemoryStream();
//set the position.
tempStream.Position = 0;
this.Response.ContentType = “application/vnd.openxmlformats-officedocument.spreadsheetml.sheet”;
Response.AddHeader(“content-disposition”, “attachment; filename=output_tempBook_new.xlsm”);
As you can see the bold lines above are not Aspose.Cells APIs, rather these are Asp.NET Response object. You will get the same issue using the above line.
Thanks for your understanding!