It would be interesting to know what went wrong with
the old
cartridge.
Is it that the drum is damaged in some way and doesn't discharge
properly usder the erasing lamps? Or is it that the wiper blade
doesn't
clean the surface of the drum properly? Or what?
Well I still have the old drum at home (keep meaning to take it to
work for recycling and keep forgetting). If you want I can don gloves
and a mask and attempt to open it to see what looks broken inside...