How to Open Xlsx in Excel 2003

1. Access the Microsoft Downloads website. Type 'Compatibility Tool' in the search box. Download the Compatibility Tool. Once it has downloaded to your computer, double click the execution file and follow the installation instructions. Click 'OK' once the installation is complete.
2. Open Excel 2003 and locate an Excel 2007 workbook. Click 'File' on the menu bar, then click 'Open.' Browse your files and locate the workbook. Click the workbook, then click 'Open.'
3. View the xlsx workbook in Excel 2003. You can work with this new format since the compatibility tool is installed.