I just got a brand new DSO4254C and it worked for a couple of hours for the initial calibration and simple tests. Then, all of a sudden, the screen went off. I waited for a couples of minutes and then, tried to reboot. Everytime I reboot, all the fron lights (buttons and VO LED) turn on but the screen never tuns on.
Did you email the gentleman referred in the previous message? Did you solve this?