Gray Screen

I have a bug where every once in a while, the program hangs and displays a gray window. If I delete the app data, it fixes the problem, but I don't want to have to delete the app data all of the time because it happens often. Thank you for any help.
Comments
Could you please give me some more details:
Is it the main application window that turns gray?
Does it hang at random or when you do something specific? At startup?
Which OS are you on?
Also, the next time it happens could you send me the app data? It might help me figure out what's wrong.
Thanks