How to Convert an XLSX File to an XLS

XLSX is the default, proprietary format for Microsoft Excel 2007, the popular spreadsheet application included in the Microsoft Office suite of productivity products. If you want to convert an XLSX file to the XLS format used in Microsoft Excel 2003 and earlier versions of the program, you can make the change one of three ways: installing and using a compatibility pack in Excel 2000, XP or 2003; using Excel 2007; or using the free and open-source OpenOffice.org Calc program.

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Convert XLSX files to XLS format.

Convert an XLSX file using Microsoft Excel 2000, XP or 2003

Step

Open your Web browser and visit http://update.Microsoft.com/. You must install all high-priority operating system updates before attempting to install the Microsoft Office Compatibility Pack that supports the XLSX format.

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Download the Microsoft Office Compatibility Pack from the Microsoft website (see Resources). Double-click the installer file after it downloads. Follow the on-screen instructions to complete the installation process.

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Open Microsoft Excel. Versions 2000, XP and 2003 all support the compatibility pack installed in the previous step.

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Click "File" in the top menu bar and select "Open." Locate your XLSX file and double-click its icon to open it.

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Click "File" again and select "Save As."

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Give the file a name and select a save location, then click the "Save as type" drop-down menu and choose the "Microsoft Office Excel Workbook" option.

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Click "Save" to save your XLSX document to XLS format.

Convert an XLSX file using Microsoft Excel 2007

Step

Open the XLSX file in Microsoft Excel 2007.

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Click the round "Office" button at the top-left corner of the screen and select "Save As."

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Give the file a name and select a save location, then click the "Save as type" drop-down menu and choose the "Excel 97-2003 Workbook" option.

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Click "Save" to save your XLSX document to XLS format.

Convert an XLSX file using OpenOffice.org Calc

Step

Open OpenOffice.org Calc.

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Click "File" in the top menu bar and select "Open." Locate your XLSX file and double-click its icon to open it.

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Click "File" again and select "Save As."

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Give the file a name and select a save location, then click the "Save as type" drop-down menu and choose the "Microsoft Excel 97/2000/XP" option.

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Click "Save" to save your XLSX document to XLS format.