Value# error
 

Hi everybody,
I have an interting problem with Excel 2003 that never happened before. I
have a Excel file with three userdefined functions and a worksheet with 6
columns and less than 30 rows most cells read info from each other and also I
have used those functions in some cells when I change a number in cell A1
worksheet is suppose to make calculations and show new data . It works fine
for fist few numbers and then it shows Value# error in most cells , and at
this point i have to close Excel and open it again and if i try the same
number it works fine until after I enter a few more number Vakllue# error
happens again.
What is wrong here ? by the way those numbers I enter are valid numbers for
those functions so it should be somthing else that casues this error . Why
when I close the file and open again it works for a while ?
Any thoughts?
--
Best regards,
Edward