Anybody wanting to view or print it needs Microsofts free Excel viewer at least.
Anybody wanting to edit or use it for calculations needs Microsoft Excel or the spreadsheet from www.openoffice.org. If it contains VBA-macro's one probably needs the real Excel, but you can try if it works with Open office.
Hope this helps.
Kees
Does anyone know if I am required to purchase some type of special developers license in order to sell a simple Microsoft Excel Spreadsheet that I create? I called Microsoft and they don't have a clue. First the support guy tells me that I have to purchase the Microsoft Visual Studio Tools for Office. Then he tells me the only requirement is for the person using the spreadsheet to have purchased a copy of Microsoft Excel - that the Visual Studio Tools for Office is not required.
Thanks.

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