I have a worksheet with formulas that need some corrections. They have these
Brackets around them and as soon as I start to edit (the dates are wrong) the
function becomes inoperational. I can't find an explanation of what these are
and would love to know how to work around them with out disabling all the
current funtionality.

Here is an example:

{=SUM(IF(Open!$R$4:$R$1001=DATEVALUE("1/31/2009"),IF(Open!$R$4:$R$1001<=DATEVALUE("2/27/2009"),IF(Open!$F$4:$F$1001=J4,Open!$W$4:$W$1001,0 ),0)))}

As soon as I click within the cell the outside brackets { } are gone and the
function no longer works. Is this a lock out function of some type?