How to Open Excel 2007 in Excel 2003

1. Click the Windows 'Start' button, select 'All Programs' and then select 'Windows Update' if you use Windows Vista or Windows 7. If you use Windows XP, open a Web browser, navigate to the Microsoft Update website (see Resources) and click 'Express.'
2. Click 'Install' or 'Install Updates' to install all High-Priority or Required updates. Skip this step if your system is already up to date.
3. Open a Web browser window and navigate to the Microsoft Office Compatibility Pack download page on the Microsoft website (see Resources).
4. Click the 'Download' button, and save the installer program to your desktop when prompted by your browser.
5. Close all open programs.
6. Double-click the icon of the installer program you just downloaded. If you use Windows XP, click 'Run.' If you use Windows Vista or Windows 7, confirm your identity, or provide your administrator user name and password and click 'OK,' when prompted to confirm your choice.
7. Check the box labeled 'Click here to accept the Microsoft Software License Terms,' and then click 'Continue.'
8. Click 'OK' to install the Compatibility Pack. If you use Windows Vista or Windows 7, confirm your identity, or provide your administrator user name and password and click 'OK,' when prompted to confirm your choice.
9. Click 'OK' after installation completes to close the installer program.
10. Open Microsoft Excel 2003.
11. Click 'File' in the top menu bar, and select 'Open.' Locate your XLSX file in the resulting window, and then open it by double-clicking its icon.