If this occurs, it may not be a hardware problem, but some sort of software conflict.
Try turning off print spooler service and making it manual.
Then try erasing the DVD-R disk (if using one) using normal windows explorer (computer=>right click on dvd drive=>click erase).
THEN burn using Nero or whatever.
This has worked for me every time even after I’ve had numerous consecutive power calibration errors. I’m using VISTA which seems to have particular problems with the print spooler in my setup. Also, note that it’s critical that you erase the DVD-R using explorer – for some reason using other programs don’t work correctly. I’m guessing that the explorer erasing does something to restore the DVD driver somehow.