New Post: PHPExcel doesn't give me results

I have a feeling that I'm misunderstanding your question.

Internally in Excel, formulae are held in English (BIFF holds tokenised, but OfficeOpenXML actually holds the English language version of the formula): it's the MS Excel GUI that translates it into function names and separators appropriate to your locale.

So your cell should contain a value of the English language version of that formula if you load it into PHPExcel (which you should be able to see if you use PHPExcel's getValue() to retrieve the value of the cell. That is, it should contain a English language names for functions, and use a comma separator for function arguments.

You only need to use locale settings if you are setting/changing a formula and wish to use French language names for functions and a ; argument separator, that's what I thought you were trying to do.

Looking at your formula though, it looks as though it should be an array formula, which isn't supported yet by PHPExcel