Some of our users experience problems with calculations in different excel
sheets. We use Windows XP and Office 2003SP2.
Simple addition formulas are not working. When an addition cell is updated
with a new number, the sum cell does not change to reflect the new
calculation. Under Options, "Automatic Calculation" is ticked, and the
cells are defined as figures.
When the file is closed and opened again, the calculation is correct. The
error is seldom seen.

Thanks in advance for your assistance