bjtklw -
You posted in a Macintosh newsgroup.
Your question is related to the Windows Vista and Windows XP operating
systems.
Compatibility of Excel files generally depends on the version of Excel, not
the operating system.
If you are using Excel 97-2003 on both the laptop and the desktop computers,
the Excel XLS files are compatible.
If you are using Excel 2007, you can choose Office Button | Save As | Excel
97-2003 Workbook to ensure compatibility.
Also, if you are using Office XP (2002) or Office 2003, you can download the
Microsoft Office Compatibility Pack for the Office 2007 file formats.
- Mike Middleton
http://www.DecisionToolworks.com
Decision Analysis Add-ins for Excel