thanks to Don Thompson for the mirror cleaning procedure. It work on my HP2600N printer (6 years old).
However, after cleaning and reassembling the unit, it printed only blank pages.
I took out the back plane 3 time in total, and recheck all cables. In the end, I believe that the reason it printed blank pages was that the optimal unit were not perfectly aligned. The lever that the spring is attached to must insert in the correct slot. Place the optical a bit to the right before sliding it left into the peg holes.
BartDo
