Word 2003 was unable to read this document. It may be corrupt.

Perhaps your computer has a memory issue. If you can't open it to run the text converter, run memory diagnostics.

If it were me, and time was of the essence and I was stumped, I'd capture the file, copy it, run it on another computer.

If copying it over fails, I hate to say it, but you'll have to do a file recovery and find some computer data service to restore the file...at a point just before it failed.