How to convert .docx files to .doc files in Windows and Mac?

M.S Windows
Microsoft has added a new file format called the Microsoft Office Open XML File Format (.docx) to Microsoft Office Word 2007, Microsoft Office PowerPoint 2007 and Microsoft Office Excel 2007. But this format is not compatible with earlier versions of Microsoft Office. With the help of Microsoft Office Compatibility Pack, you can convert .docx files to .doc files very easily and you can open and save Office Open XML Formats in earlier versions of Microsoft Office.

By installing the Compatibility Pack in addition to Microsoft Office 2000, Office XP, or Office 2003, you will be able to open, edit, and save files using the file formats new to Word, Excel, and PowerPoint 2007. Before installing compatibility pack, users of Microsoft Office XP and 2003 must install all High-Priority updates from Microsoft Update.

This Microsoft Office Compatibility Pack supports Windows 2000 Service Pack 4, Windows Server 2003, Windows Vista, Windows XP Service Pack 1, and Windows XP Service Pack 2.

Download Microsoft Office Compatibility Pack

Mac
For Mac beta version of Microsoft Office Open XML File Format Converter is available. This beta version expires on December 31, 2008. This Open XML Converter can convert Open XML files to a format that is compatible with Microsoft Office 2004 for Mac and Microsoft Office v. X for Mac.

With this converter you can convert Open XML file formats like .docx, .docm, .pptx, .ppsx, .potx to a format that is compatible with Microsoft Office 2004 for Mac and Microsoft Office v. X for Mac. But remember, You must use Office 2004 11.3.4 or later, or Office v. X 10.1.9 or later to open these converted documents. Also this version of converter is not compatible with Microsoft Office 2008 for Mac.

Download Microsoft Office Open XML File Format Converter for Mac