Hope I am in the right form to ask this question.....

I have excel 2007 NEW and alot of changes but how does one
put a formula in for to protect the file??????
I did use protect file in the format and it protected it--- butt
I am asking how does one protect the file when you have to
put in a number and have to add to the file????
Hope I am explaining it right.....file is protected butt one has to
add three numbers to the file....is there a formula for this????
After the fact that so one can run the file butt cannot change the file....
Thank you