Conditional Formatting

[Alan Hutchins]

Hi,

I have an input model which I have populated with data in each cell by
entering =SUM(Balance_Sheet_Retrieve!A1), and so on. Some of the cells will
be locked so they cannot be changed and these are coloured light green. Input
cells - which can be changed are coloured light yellow.

What I would like to do is use conditional formatting to change the
background colour of any input cell which no longer uses the exact original
formula - so, for example:

if the cell just has a value OR has a different formula (even if it is the
original formula plus a new one, or plus/minus a value)

Then I want the background colour to change to light blue.

I did think of using a worksheet change event, but I discounted that because
not every cell will be coloured, and the input cells are spread in various
locations.

So, is this possible, and if so, how do I do it?

I did find something on David MacRitchie's website using a function in the
conditional formatting argument, but I couldn't get it to work to check the
formula in the cell.