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Save as XLSB and XLS Format


Please add the option to save in XLSB and old XLS format.


richardtallent wrote Apr 2 at 6:56 PM

The .XLSX format has been the standard now for over 10 years, and this would be a MASSIVE undertaking that would only benefit a tiny number of people.

If you need support for old binary formats, your best bet would be NPOI (, or possibly ExcelLibrary ( I've used NPOI before, it doesn't support as many features, but works well enough.