Hi
I need some help on overidding the data via checkbox.

Basically i am working on a spreadsheet that is doing two things 1) its allowing the user to choose between 1 to 3 number or N/A from the list validation option and 2) there is a checkbox if one selects that all the columns that have the formula will become N/A irrespect of data in it.

I am using the following formula in the list validation option
a3 is the check boc
E5 =1
E6= 2
E7 = 3
E8=N/A

=if(a3=true, $E$8, $E$5:$E$8)

The issue I am having with this is, if I start selecting something from the drop down and half way I realize I need to check the box, it will only make it E8 value for the cells I have not touched and the ones I have already selected the drop down value it will remain. However I want it to override the value to E8 irrespect.