Hi, the U88 fault is a system recovery function normally due to corrupted system files on the recorder.
First we need to eject the DVD tray so the machine knows there is no DVD inside, in many cases the eject button will not work (but check if the eject button will allow you to remove a disk from the tray).
Where the eject button doesnt work, place the unit in standby, and then press and hold Stop and Channel Up buttons, on the main unit simultaneously for about 5 seconds (the DVD tray should eject).
If this doesnt work, turn the power off at the wall hold the two buttons and switch it back on at the wall.
Once the DVD tray has ejected, restart the machine by powering off the wall, and leave the unit for 15 minutes and it should recover from the U88 mode, if this doesnt work you need to send the unit to a service centre as most likely the main board has failed.