I am using the following if statement:

=IF(AND(ISBLANK(E5),ISBLANK(F5)),"",E5+F5)
I want to paste that formula for the entire column, which I think I have done correctly and the cell references change the wale they are suppose to, BUT instead of being blank the way they should be, they come up and say #VALUE. Now when I enter numbers in the reference columns the addition works correctly, but why is the #VALUE coming up?

Thanks, Chester