I turned my phone off briefly today and when I turned it back on, it hangs on boot at the Samsung logo with 3D010017 in red across the top of the display, keypad light flashes, it will NOT work at all. Removing the battery did not work, removing the SIM, trying to boot without it then reinserting SIM & booting again did not work. Battery & contacts look good, new battery in fact, SIM card also looks fine, all clean. Phone & components haven't sustained physical or water damage. If anyone else has had this problem, I'd really like to know what caused it before calling customer service and jumping through hoops. Thanks!