Spreadsheet doesn't "view" with shading and text colors

[Excel spreadsheets]

While viewing the spreadsheet no colors appear, yet when the print preview is
accessed everything is in color as it should be.

 

[Page S]

I recently encountered the same problem. If I format cells in a color other
than the automatic(format/font/plum by example) or if I format/pattern/choose
a color and then press OK everything reverts to the automatic color (black
w/white background). If I then email the document to someone else they see
the colors, the same way you or I can see it in print preview. Haven't been
able to figure out the cause.