Excel 2003 Crashing Weekly

[AndyTC]

Hello,

I have created an excel spreadsheet that tracks movement of our personnel.
It has around 10 tabs, with 100 colummns of data, 15 rows, not a huge
amount of data.
This spreadsheet has started to crash almost weekly in which the user
has to rebuild it, by copy and pasting the data into a new spreadsheet.
We also pulled out all formulas to see if that helped.

These are the errors my user gets:

Excel found unreadable content in '03.22.2010 Movement Tracker.xls'. Do
you want to recover the contents of the workbook? If you trust the
source of this workbook, click yes.

Then I get the following:
"Repairs to '03.22.2010 Movement Tracker.xls'

Errors were detected in file 'G:\Daily\Movement Tracker\2010
Tracker\Back Ups\03.22.2010 Movement Tracker.xls'
The following is a list of repairs:

Damage to the file was so extensive that repairs were not possible.
Excel attempted to recover your formulas and values, but some data may
have been lost or corrupted.


Any ideas whats going on? It's a simple spreadsheet.
This is excel 2003.