Error message: Excel could not save all the data and formatting

[exceluseratcci]

I got the following error message while trying to save my work on a spreadsheet on my machine with Excel 2003:

"Excel could not save all the data and formatting you recently added to Financial Report.xls.

To return to your workbook without saving click Cancel.

If you want to continue saving changes without repairing the problem, click OK."

This spreadsheet is located on a shared drive where the primary user has Excel 2010.

Any ideas for how I can diagnose how to find the source of this problem and repair it?

Thanks