I have installed ciss on my canon ip2770, i had used it for 4 days but now it says both cartridges not recognize how can i fix it

SOURCE: Canon i560 printer

I have similar problem. I found this solution that may help you. My problem insists tho.

>>> 5 flashes indicates a faulty printhead or possibly a problem with the p/head contacts. Try removing the head which is easier if you take the cartridges out first(no tools required) and re-seat it having checked the contacts for dirt.

If that doesn't work it may be that the waste ink tank is full. Try this ...
Canon S9000, S300, S400, i550, i560, i850, i860, i865, i9100, i9950, PIXMA iP3000 above,
1. Turn off printer
2. Hold down Resume button and press Power button.
3. Keep holding down Power button and let Resume button go.
4. Press Resume button 2 times then let BOTH buttons go.
5. Green lights will flash and then stop blinking.
6. When green lights are solid, press the Resume button 4 times.
7. Press the Power button and the printer should turn off, if not, press the Power button once more.
8. Your printer should respond as normal.

SOURCE: error and power light blinking.

Here is the Waste Tank Full reset.

Canon BJC-50 BJC-55 BJC-80 BJC-85 M40 M70 
1: Unplug Power Cord
2: Hold POWER and RESUME buttons
3: Plug in Power Cord 
4: Release buttons after the printers starts up 
5: Hold CARTRIDGE and RESUME 
6: Press POWER 
7: Release all buttons after the beeps 
8: Press CARTRIDGE 16 times 
9: Press RESUME 
10: Unplug the Power cord

SOURCE: Canon 1560 error - orange light blinking 5 times

It's mean "Print head not installed/Defective print head".First open cover and remove the ink cartridges.Then open holder and remove the print head.Clean the contacts on printer and print head using piece of cotton and some alcohol.Then put back all again.If the problem persist you need to replace the print head.It's part number now is QY6-0064, because the old QY6-0042 is discontinued.

Clive

• 4362 Answers
• Posted on Feb 10, 2010

SOURCE: Canon i9950, Operator error,5 amber blinks

1. Turn off Canon i550, i560, i850, i860, i865, i9100, i9950 Printers
2. Hold down Resume button and press Power button.
3. Keep holding down Power button and let Resume button go.
4. Press Resume button 2 times then let BOTH buttons go.
5. Green lights will flash and then stop blinking.
6. When green lights are solid, press the Resume button 4 times.
7. Press the Power button and the printer should turn off, if not, press the Power button once more.
8. Your Canon i550, i560, i850, i860, i865, i9100, i9950 Printers should respond as normal.

SOURCE: ink cartridges cannot be recognized in canon printer

Hello!
Remove the cartridges and gently wipe the cartridge contacts with a dry cloth, then put them back in. Then, hold the "resume" button for 10 seconds for each cartridge, that should reset them.
If that doesn't work, one of your cartridges (sadly) needs to be replaced.