I replaced the black ink cartridge yesterday and it seemed to print fine. Today it is not dispensing any ink. (I also just replaced the print head a few weeks ago.)

It seems print head clogged,this issue not related with cartridge, perform clean print heads 3-4 times & chk, if no result replace the print head (CN642A).. I won't suggest for manual cleaning for this print head unit.. Thanks for listening me..

Not normally but the black print head nozzles maybe blocked.
Inkjet printers need to be used frequently to prevent ink drying out and blocking the print head nozzles.
If the print head cleaning maintenance routine does not clear the blockages, then print head needs replacing, but it may be expensive.
It may be more cost effective to buy a later model and better printer than replace the print head.

Yes sounds to me like one of your ink cartridge is empty. Replace and try again.

Always try replacing the ink cartridges first.

It sounds like the print heads in the 7780 are bad. Don't confuse the ink cartridges with print heads. The cartridges fit inside the print heads. You will need to change the heads. Here is a link to HP's how-to.
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00841890&tmp_track_link=ot_faqs/top_issues/en_us/c00841890/loc:1&lc=en&dlc=en&cc=us&lang=en&product=2512010

Could have the same problem with the Dell.

did you remember to pull the tape off the print head before you installed the new cartridge?

The Epson CX9400F printer seems to require replacement of all the color ink cartridges, even if only the Black is empty.

I print almost exclusively in Black, but with my first change of Black, I was forced to change all the color. At the time I thought Epson did not provide completely filled color ink cartridges.

Just yesterday, I replaced Black and the printer complained it did not recognize the rest of color cartridges. So I replaced all the other color ink cartridges and now it works fine.

You might want to check out www.clickinks.com for cheaper, mail order alternatives which are Epson ink compatible, if you are not in a hurry.

ew

Try unplugging it for an hour first.
Thanks,
Lee

If you haven't done so, I would try another new cartridge. It is entirely possible (and occurs frequently) that you got a bad cartridge. Assuming you removed the tape from the cartridge before putting it in, this is generally indicative of either a bad cartridge, bad print head, or that heads or ink tanks may need cleaning.

The Canon support page for this printer is at:
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=SupportDetailTabAct&fcategoryid=238&modelid=10444

However, as Canon pages come up as generic pages (without the text I input for you), you will have to type in "missing black ink" (without quotes), to see the material they have posted in this regard. You will find instructions there in regard to how to clean the print heads, etc., if that is necessary. However, I would definitely try another cartridge first, especially if you haven't had that much use on the printer, such that you think these other measures may be necessary.

Please post back if you need further help, otherwise thanks for rating FixYa!

did you remove the seal of new catridge. bye

First with a clean soft cloth and a very small amt of alcohol clean off the underside of the printer carridge (the holder for the print heads) also where the print heads cleaning station is clean out any large masses of congealed link. Then remove the ink cartridge in question and with a pencil eraser gently rub the contacts and both the cartridge and the carridge replace the cartridge. Using the software tools for the printer clean and align the printheads ( if there is an option to do so). If this dosn't fix the problem try a different ink cartridge.