Windows Works 4.5a

My wife typed a long letter, then saved it to the a: drive. Upon returning to the file, it opened with a bunch of machine language symbols (squares, y's, etc.). This has never happened before. Other .wps files on the 3 1/2" diskette open just fine. Is there anyway to retrieve this long and precious letter?

 

And the file was created and saved on the same machine? Or did she type is somewhere else, save it to floppy and open on another machine?

 

The letter was composed, saved, and reopened on the same machine. I copied the file to another diskette and get the same results on my computer at work.