Use Excel 2007 with earlier Excel versions
How to keep new Excel workbooks accessible for other users
Work in Compatibility Mode
After you've installed Microsoft Office Excel 2007, you may want to know how you can continue working with workbooks that are created in an earlier version of Excel, how you can keep these workbooks accessible for users who don't have the current version of Excel installed, and how the differences between the versions affect the way that you work.
For backward compatibility and collaboration with earlier versions of Microsoft Office Excel (Excel 97-2003), you can use one of several ways to exchange workbooks between the different versions.
In Office Excel 2007, you can open a workbook that was created in an earlier version of Excel and work in Compatibility Mode so that the workbook remains in a file format that can easily be opened again in the earlier version. An Excel 2007 workbook can also be opened in an earlier version of Excel by using file converters that can be downloaded.
And if you decide to convert the workbook to the current file format, you can always check the converted workbook for compatibility with earlier versions of Excel, so that you can make the necessary changes to avoid the loss of data or fidelity that might occur when that workbook is opened in an earlier version of Excel.
Work in Compatibility Mode in Excel 2007
In Excel 2007, when you open a workbook that was created in an earlier version, it is automatically opened in Compatibility Mode, and you see Compatibility Mode in square brackets next to the file name in the Excel title bar (title bar: A horizontal bar at the top of a window, dialog box, or toolbar that shows the name of the document, program, or toolbar.).
In Compatibility Mode, any new or enhanced Excel 2007 features are not available when you work in a workbook, which prevents the loss of data and fidelity when the workbook is opened in an earlier version of Excel. Also, rather than using the current XML-based file format (.xlsx), the workbook is saved in Excel 97-2003 file format (.xls), a binary file format that is easily opened in an earlier version of Excel.
Unlike other 2007 Microsoft Office system programs, such as Microsoft Office Word 2007, you cannot manually turn on Compatibility Mode in Excel, and you don't have the option to include any new features when you work in a workbook in Compatibility Mode.
If you no longer want to work in Compatibility Mode, you can convert the workbook to the current file format.
Use file converters in earlier Excel versions to open an Excel 2007 workbook
Specific updates and file converters are available on Microsoft Office Online that can help you open an Excel 2007 workbook in an earlier version of Excel (Excel 97-2003). If you have not yet installed the updates and converters, when you try to open an Excel 2007 workbook, you may be prompted to do so.
After installing the updates and converters, all Excel 2007 workbooks can be opened so that you can edit and save them without having to upgrade your version of Excel to Excel 2007.
Excel 2007-specific features and formatting may not be displayed in the earlier version of Excel, but they are still available when the workbook is saved and then re-opened in Excel 2007.
Download and use file converters
Convert a workbook to Excel 2007 file format
When you open a workbook that was created in an earlier version of Excel, and you no longer plan for anyone to work on this workbook in the earlier version, you can convert the workbook to the current Excel 2007 file format.
When you convert to the current file format, you will have access to all of the new and enhanced features and functionality that Excel 2007 offers, and the file size will be smaller.
To convert the workbook, you can:
Convert a workbook to the current file format
Check an Excel 2007 workbook for compatibility with earlier versions of Excel
To ensure that a Excel 2007 workbook does not have compatibility issues that cause a significant loss of functionality or a minor loss of fidelity in an earlier version of Excel, you can run the Compatibility Checker. The Compatibility Checker finds any potential compatibility issues and helps you create a report so that you can resolve them.
Important: When you work on a workbook in Compatibility Mode, where the workbook is in Excel 97-2003 file format (.xls) instead of the new Excel 2007 XML-based file format (.xlsx) or binary file format (.xlsb), the Compatibility Checker runs automatically when you save a workbook.