I suppose I have to say that I've been very lucky. I've been using a computer gradebook of one variety or another for fifteen years, and until today I've never had a problem. Unfortunately today I did have one. My gradebook file has been corrupted. The data from one class is gone, both in my original file and in the backup. My very wonderful Education Computing Strategist is online with the tech support people to see if we can unscramble the data. Barring that, well, I have the overall grades recorded on paper, just not the grades for individual assignments. I'll still be able to assign grades. The sad thing is that most of my students don't care what those grades will be.