Method One
By default, the suffix name of the two build files is different, and 2007 uses a new file name format (which can also be set to a compatible format), such as: 2007 of the Excel file suffix name is. xlsx, and 2003 of the word filename suffix is. xls; 2007 of the Word file suffix name is. docx, and 2003 of the word filename suffix is. doc.
You can do this if you want to open a file with a. doc suffix of 2003 by default:
Right-click the suffix name. doc file, open the way → Select the program, in the Open dialog box, select the Word 2003 program, and then "always use this way to open the file" check, and finally click OK. You can do this once for an. xls file.
Method Two
Click "Start-Run" to enter the installation path for Excel 2003, for example (including quotes with the beginning):
"C:Program FilesMicrosoft OfficeOffice11Excel.exe"/regserver
Other Office components can do the same. This way, double-clicking any Office document opens by default with Office 2003, and Office 2007 can be opened from start-Program, with both worlds.