To open Microsoft Office Word .docx or .docm files with Microsoft Office Word 2003, Word 2002, or Word 2000, you first need to install the Microsoft Office Compatibility Pack Office Word, Excel and PowerPoint File Formats. Simply download and run the executable file located here. File format converter
By using the Compatibility Pack you can open, edit, and save Office Word 2007 documents in previous versions of Word. You cannot open Office Word 2007 template files that were saved in .dotx or .dotm format.
If you just need to convert a single .docx file, and you don’t know how to install programs, or do not have administrator access to do so, then follow these steps. Point your web browser to www.docx-converter.com. Upload your file, select your preferred format (.doc), and enter your email address. In a moment, you should get a note containing a link to download the converted file. This is a free service, so please do not abuse it.