Data corruption in Race Director can happen on a computer where you lost power or you shut down with Race Director still open. As you are using Race Director, a full backup of your race happens after you exit all of the screens where you're updating race setup, participant updates or scoring data. To return your system to the last backup point, find the Recover Data selection in the Race Director install folder. After that little process runs, start Race Director and it will go through about 20 steps to reset the data bases. Once that is done, you will be positioned into race number 1. Next, use the Maintenance -> Force Conversion option. Re-open the race you were in and all should be well.