I have a function in an addin i created which does some basic calculations
which is loaded and saved however when i open a spreadsheet that was saved
with calls to this function I get the #Name error

the addin is loaded when I open excel because if i add any more of these
functions into the spreadsheet it works, on loading the spreadsheet Excel
seems to process the sheet before loading the addins so fails

I works fine on some computers but not on others