I get ink system failure Oxc19a0023 on my HP c6380 all-in-one. I have removed the cartridges and cleaned the three points on the print head. I've unplugged and plugged back in. I still get the same error.

1) connect the printer directly to wall outlet..
2) try different wall outlet as well
3) try with a different set of ink cartridges...
if issue persists continue with the following ts steps.
4) Reset the printer
The error message might disappear after you turn off the printer and then turn it on again. After you make any adjustments to the cartridges or the printhead, reset the printer in order for the error message to clear completely. Follow these steps to reset the printer.
a) Press the Power button ( ) to turn on the product.
b) With the product turned on , disconnect the power cord from the rear of the product.
c) Unplug the power cord from the wall outlet.
d) Wait at least 15 seconds.
e) Plug the power cord back into the wall outlet.
f) Reconnect the power cord to the rear of the product.
g) If the product does not turn on by itself, press the Power button ( ) to turn it on.
If these steps resolved the issue , you do not need to continue troubleshooting.
If the issue persists , continue to the next solution
5) Remove, clean, and reinstall the printhead
If the previous solutions did not resolve the problem, the printhead might be installed incorrectly, or there might be ink or debris on the printhead electrical contacts. Follow these steps to check and clean the printhead.
Step one: Remove the printhead
a) Press the Power button to turn on the product.
b) Open the cartridge access door.
c) To remove each cartridge, press the tab on the front of the cartridge to release it and remove it from the slot.
NOTE: Do not leave the cartridges outside the product longer than 30 minutes. Doing so can result in damage to both the product and the cartridges.
d) Lift the latch handle on the carriage until it stops
e) Lift the printhead straight up to remove it
Step two: Clean the printhead
There are three areas of the printhead that need to be cleaned: the plastic ramps on both sides of the ink nozzles, the edge between the ink nozzles and the electrical contacts, and the electrical contacts. Follow these steps to clean the printhead.
CAUTION: Do not touch the ink nozzles. Do not touch the electrical contacts with your finger. Use only cleaning materials to touch the electrical contact areas
a) Gather the following cleaning materials:
Several clean, lint-free cloths or papers. Coffee filters and glass-cleaning cloths work well.
Distilled or bottled water. Do not use tap water, because it can contain contaminants that can damage the printhead.
b) Lightly dampen a clean, lint-free cloth.
c) Use the damp cloth to wipe the electrical contacts from the bottom to the top. Do not go past the edge between the electrical contacts and the ink nozzles. Repeat this motion until no ink remains on the electrical contacts
d) Use a fresh, lightly dampened, lint-free cloth to wipe any accumulated ink and debris from the edge between the ink nozzles and the electrical contacts
e) Use a fresh, lightly dampened, lint-free cloth to wipe the plastic ramps on both sides of the ink nozzles. Wipe away from the nozzles only
f) Dry the previously cleaned areas with a clean, dry, lint-free cloth before proceeding to the next step.
g) Lightly dampen a fresh, clean, lint-free cloth with bottled or distilled water.
h) Clean the electrical contacts inside the product by wiping them from top to bottom. Repeat this motion until no ink remains on the electrical contacts.
i) Dry the area with a clean, dry, lint-free cloth.
Step three: Reinstall the printhead
a) Raise the latch handle, and then reinsert the printhead
b) Carefully lower the latch handle before reinserting the cartridges.
NOTE: Leaving the latch handle raised can result in incorrectly seated cartridges and printing issues. The latch must remain down to install the cartridges correctly
c) Using the colored shape icons for help, slide the cartridges into their appropriate slots until they snap firmly into place in the slot.
d) Close the cartridge access door.

6) Reset the product
Steps are given above
7) Replace the printhead
8) if it does not work Service the product...

Hope this works...