Everytime I type in the sum formula, it is exactly right, according to the
help menu. When I get my answer, It is always zero, I do not have any numbers
in my equation that are negative so I do not see how that is possible. I
thought maybe I was typing it in wrong, but then I used the autosum and got
the same answer. In the cell with the zero, there is a little green triangle
in the top left corner and I move my mouse over it and it says "This cell
contains a formula and it is not locked to protect it from being changed
inadvertantly." When I click help on this error, I only get a blank white box
that says nothing. My only option is to lock cell, which does not help at
all. Please help me! Thank You!