BB Curve :: Turning Itself Off - White Screen Of Death

Right, I've had my blackberry for a few months now, it was bought from someone else. Only recently, my phone has been turning itself off and giving me the "white screen of death" but I've always managed to get passed it by removing the battery then restarting it. But today, it has turned itself off, reloaded to the main screen where it then freezes, the screen goes white and it says "app error 523 - reset". Ive clicked reset about a billion times and it keeps doing the same thing over and over again. I downloaded blackberry desktop/device software but it won't find my device. I tried that app wizard loader thing, but that didn't work either. And yes, my phone is charged.