Use the Example VI Open Excel and Make Visible.vi to open Excel. Wire up the Application ref to proberty WorkBooks and then cascade to Method Open. Open the Excel workbook that contains your macro functions.
Then wire Application ref to Method Run. There you can specify the name of the macro and any arguments. A variant will be returned if you call a function. I am using LV6.1 and Excel XP.
You will need a Visual Basic compiler to make a DLL out of your code.
Michael
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