in the program you want to use, goto File > Open, navigate to the location of the file you want to open, make sure the "Files of type" shows "All files *.*" and then highlight the file and click Open.
However, if the file type you want to open with that program is incompatible with the program, it will not open, or will just display rubbish information.
Mark
How do I open a file from word to works.

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