In Microsoft office 2007, the default file format contains “x” like docx. But when file saved as docx in office 2007, it cannot open in office 2003.
But now no problem – Microsoft gives File Format Coverter to convert office file types. This small tool supports to all of the office 2007 file formats.
after installing this, you have to restart machine, and now right click on any office 2007 file and click convert. Now a office 2003 type file will be build in same path