Open in XL 2003, when you close it, it should, ask you if you want to
convert the file to the latest version of Excel. If it does not, go
under 'File' and select 'Save As'. The 'Save As' dialog box will open.
At the bottom of the dialog box is a pull down menu labeled 'Save as
type'. Select 'Microsoft Office Excel Workbook (*.xls)' You will have
several options including past versions of Excel to choose from.
Hope that helps...