If the high contrast setting is turned on you won't see the fill colour.
There's information in the following MSKB article:

OFF: Changes to Fill Colour and Fill Pattern Are Not Displayed
http://support.microsoft.com/?id=320531


anonymous wrote:
The problem I have with my Excel is that it will not
display background colour in the cells. It shows the
colour when you do a print preview and also when you open
the files on another computer.

i am using office 2002 and windows xp sp1


--
Debra Dalgleish
Excel FAQ, Tips & Book List
http://www.contextures.com/tiptech.html