• If you turn off your console during the welcome screen or switch test screens, make sure it is in deep sleep mode for at lest 10 seconds, it won't recognise discs until you do it. If you have any doubts, unplug the console for 10 seconds.
• If you get stuck in a Programming - Verifying loop for more than 10 cycles, it is likely that there is an installation problem with the S wire. You have to turn off the console to fix this, but make sure you never turn it off before trying at least a dozen cycles. We got two reports of this behaviour and it was fixed both times.
• Make sure the switch pads are not in contact with any metal part of the Wii, including shielding. If there is such a short circuit, the fuse next to the X point can blow and drive won't spin or eject anymore until you fix the fuse.

Via Team Cyclops