HP Photosmart 3210. All colors printing fine, except black. New cartridge didn't help. cleaning contacts no different...

(The obvious) Replace the black cartridge. Even if ot says you have ink you could have a faulty cartridge, even if it has worked fine in the past. (The not so obvious) Clean your printheads/nozzles. Repeat the process a few times.

http://h10032.www1.hp.com/ctg/Manual/c00485555.pdf

the nozzles are clogged most likely. try to clean it by using the software provided. another thing is try to align the print heads. that's also included in the software for the printer.

Remove the magenta cartridge, and try cleaning the head with alcohol, maybe with a small paint brush or an acid brush. It sounds like ink has dried and plugged up that head.

must be dryed ink on ink cartdrige, or dirty print-head (ink cartdrige) conntector.
try these :
To clean the print head from the control panel
1. Load letter or A4 unused plain white paper into the main tray.
2. Press Setup.
3. Press 5, then press 2.
This displays the Tools menu and then selects Clean Printhead.
or
To clean the ink cartridge contacts
1. Unplug the power cord from the back of the HP All-in-One.
2. Lift the ink cartridge access door.
3. Squeeze the tab below an ink cartridge to release the latch inside the HP All-in-One, and then lift the latch.
4. Inspect the ink cartridge contacts for ink and debris buildup.
5. Dip a clean foam rubber swab or lint-free cloth into distilled water, and squeeze any excess water from it.
6. Clean only the copper-colored contacts.
7. Place the ink cartridge back into the empty slot and press down on the gray latch until it clicks into place.
8. Repeat if necessary for the other ink cartridges.
9. Gently close the ink cartridge access door and plug the power cord into the back of the HP All-in-One.

These steps is printer manual on pag 99 and 100

Remove the color cartridge, it will run on "Ink economy mode" or something like that. It WILL print from windows but the copier wouldn't work, displaying error. The copier needs both cartridges installed to work.

clean the connector between the cartridge and the brownish part in the printer where the cartridge touches. it might be dirty and thus not enabling the connection with the black

It is possible. You will have to go into the properties of the printer you're using. Assuming you're using WinXP, go to Start>Printers and Faxes and right click your color printer. Choose Printing Preferences. Using my HP Photosmart C3100 as an example, I would next choose the Color tab and under Color Options, choose the radio button that says Print In Grayscale. That will do it.

Look at the posts on "black ink problem" later on this site (mostly Dec).

This appears to be a very common issue with this model and results from a serious design error.

You may need to force the blockage out of the black ink feeder system, a messy process.

The 9 offers on "black ink problem" give various suggestions: try the top one.

There are some print head cleaning modes you may want to try.
In your menus , look around for those and run the print head calibrations and cleaning procedures.
Also with the printer unplugged. Dampen an cloth with some rubbing alcohol and remove the print cartridges, lightly clean all the contacts with that damp cloth.
They may just have some ink on the contacts giving you a false failure message.
Hope this helps you out. They can be fickle.