Solver - Evoloutionary, how to apply upper and lower bounds

Hi Guys,

I'm trying to use the Evolutionary function on Solver. From my reading I believe it can Max a cell even if it, or the constraints have 'if' function feeding into them. When i try to run it I get the error

"
All variables must have both upper and lower bounds.

The Evolutionary Engine and Multistart option require that you
specify both and lower bounds on all the Variable Cells.
"

The problem is I can figure out how to apply the upper and lower bounds to the Variable Cells.
I'm sure it something easy, I feel silly asking.

Thanks Guys,

Simon