1. Press 1, 3, 5, 7 simultaneously, enter password 649, wait for reboot (it takes 30 seconds or so to start)

OR

  1. Press the Menu key
  2. Press 3 - Settings
  3. Press 2 - Advanced
  4. Enter 649 and press Enter softkey
  5. Press 1 - Admin Settings
  6. Press 5 - Reset to Defaults
  7. Press 4 - Format File System