Why printer don't work but continuously saying: CARTRIDGES NOT ENGAGED
About a month ago, I replaced the black ink cartridge on my HP Laser Jet 3600n printer.
Since that day it did not print again. Every time I closed the printer's front door thinking it will start to print again, the following message comes on the printer's screen: 'CARTRIDGES NOT ENGAGED. Open and close front door'.
I have tried closing this printer's front door numerous times and the same message re-appears. I have removed all four cartridges a number of times and fixed them back in but the above message on the screen still remains the same each time I close the front door.
Can someone help me with this nagging problem?
When it is not faulty, as it was in the past, the print quality of this machine is excellent and unrivalled. Thanks in advance.