1. Create a function in Excel 2007 itself (no import, just type a short one). Does it stick?
2. If yes, create all functions and copy/paste the contents into them.
Kees
I have Excel 2007 in Vista. I created an excel add-in file for a friend using the xla extension (for older excel versions). It adds steam table functions to use in spreadsheets. It works just fine on my Vista laptop.
I sent it to my friend who installed it in Excel. It shows up as an add-in but doesn't work. Opening VB, the Visual Basic Project shows up but without the module with the functions/code in it. We exported just the module as a BAS file and tried importing it into the VBAProject and after three tries, magically three copies showed up in the VBAProject. Deleting the extras the program's functions worked. Close excel, open it again and poof, no more module/code. Does anyone have any suggestions to get it to stick.

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