Maybe disaster is too great a word. On the downside, I didn't have any good version of my file. I back my jump drive to my c: drive and my c: drive backs up automatically to my external drive, but all three files had the corruption. I don't know how long ago it happened, but it was before all the backups occurred. On the plus side, only a few pages need to be rewritten, as not as much of my file was damaged as I though.