Unfortunately I don't think you can.
There have been a lot of complaints about shading of cells in XL2007.

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Regards
Roger Govier
> using excel 2007, using find-go to special formulas, the shading on the
> formula cells is the lightest blue and very difficult to see. Can I
> change this fill color format?
> charlie
Charlie Woll - 19 Feb 2008 16:24 GMT
Thanks Roger, not a useful function without better shading!
charlie
> Unfortunately I don't think you can.
> There have been a lot of complaints about shading of cells in XL2007.
[quoted text clipped - 3 lines]
>> change this fill color format?
>> charlie