Canon LBP3000 - Page 249

Replacing the Toner Cartridge
5-6
Routine Maintenance
5
4 Align the protrusions on the left and right ends of the toner
cartridge with the toner cartridge guides in the main printer,
and push the cartridge all the way to the back
aa
aa
, then pull it
down towards you
bb
bb
.
a
b