yearfrac problem
 

I have Excel 2002 in spanish. I created a system that calculates the interest
service from varios kind of debt from a Company. It requires to use the
yearfrac function to calculate how many days between each payment are to be
taken into account for the calculation of interest, given the diversity in
the types of bonds that this company issued.

The system requires to open for example 3 BIG!!! workbooks at the same time
(stock, cupons and proyected service) stock and cupon feed proyected service,
so they are linked. The function yearfrac is used in the workbook "cupons".

I have activated the add-ins required to use yearfrac. However when I open
the 3 workbooks I find that every place where I used the function yearfrac in
the woorkbook cupons the system substituted it for another name using the
path of the program ATPVBAEN.XLA , and aditionally it introduced the latter
as an external link!!!!! which I did no create.

After that the workbook "cupons" give me the error #Value where it is
suppose to calculate yearfrac!!!!.

Could somebody please help me and tell me how to correct it and why it
happen!!!!!

Thanks a lot!!!

Adriana