Thanks for your posting and using Aspose.Cells.
We were able to observe this issue by opening the output excel file in Microsoft Excel 2013. The output excel file opens fine in Excel 2010 though.
We have logged this issue in our database for investigation. We will look into it and fix this issue. Once the issue is resolved or we have some other update for you, we will let you know asap.
This issue has been logged as
- CELLSNET-43802 - Excel file corrupts on opening and re-saving and does not open in Excel 2013