How to make HP Deskjet 840 C compatible with IMac

SOURCE: Printer won't print

I guess its compatible, maybe you did not install the correct driver of the printer, u can download the correct driver here;
http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?product=1139325&lc=en&cc=us&dlc=en&submit.y=3&submit.x=4&lang=en&cc=us
just click the Operating system.

Please uninstall the old driver of the printer so that everything is fine. after unistalling you need to restart the computer.

SOURCE: blinking lights on my hp deskjet 840c printer

There should be some error .So you know how to remove the catridges just remove it n re insert it properly.If there are any paper jams try removing it also.and by the way if you haven't installed the drivers for HP deskjet this problem may arise.So make sure you ahve don this.Also this can be happened if the printer have some hardware problems.So none of this solutions are working its better to consult it with an expert.

SOURCE: Hp deskjet D2560,incompatible cartridge

pls check your cartridge carrrier.

SOURCE: My printer Hp 840c is not printing colour prints?

Friend try the utilities through cleaning nozzle check and head cleaning

SOURCE: printer hp deskjet 840c blinking

Depends which red blinking light. I assume the red light is the resume light. The green light is the power light. If the Power and the Resume light are blinking alternately, then you have a paper jam somewhere in the printer. remove the paper jam and you should be fine.