"Andy" wrote:
Can somebody tell me what is XLL files, how to create it
and how to use it and also where to use it.

They are native DLLs exporting a few defined functions, typically written in
C. XLLs are typically used in professional environments (e.g. finance,
engineering) to provide custom worksheet functions for Excel.

A small working example wll help a lot.

I have collected some links he
http://www.jens-thiel.de/archive/excel.html

Jens.

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