Green light flashes, will not print. Checked all

This is how I just fixed a Canon MP800 all in one with the flashing green & orange lights (a series of 9) & error code 6800. Left it UNplugged from the electrical outlet over night. Plugged it in the next day & turned it on. First window now showed a different error iu30 or some such, & showed a graphic of the ink cartridges with problems recognizing them. Held down the RESET button until the graphic showed the first cartridge as ok, (the picture will change), let go and held down the RESET button again for the next cartridge & so on until all 5 were ok. The screen then changed to a menu asking me what language I would like. Used the arrow keys around the OK button to select English. Then pressed OK for that language. The screen then changed again & said it would have to do a printhead alignment & to put paper in the printer. I put paper in & pressed the OK button again. It took about 5 minutes for the print head alignment. The paper with the alingment marks came out printed correctly. The next screen showed a normal screen which usually defaults to the Copy properties. Turned the printer off & on again a few times & everything was fine. Have no idea how long this will last or what caused the problem, but it is fixed for now. Related Problems & Solutions Filter Problems by Issues: This is how I just fixed a Canon MP800 all in one with the flashing green & orange lights (a series of 9) & error code 6800. Left it UNplugged from the electrical outlet over night. Plugged it in the next day & turned it on. First window now showed a different error iu30 or some such, & showed a graphic of the ink cartridges with problems recognizing them. Held down the RESET button until the graphic showed the first cartridge as ok, (the picture will change), let go and held down the RESET button again for the next cartridge & so on until all 5 were ok. The screen then changed to a menu asking me what language I would like. Used the arrow keys around the OK button to select English. Then pressed OK for that language. The screen then changed again & said it would have to do a printhead alignment & to put paper in the printer. I put paper in & pressed the OK button again. It took about 5 minutes for the print head alignment. The paper with the alingment marks came out printed correctly. The next screen showed a normal screen which usually defaults to the Copy properties. Turned the printer off & on again a few times & everything was fine. Have no idea how long this will last or what caused the problem, but it is fixed for now. Related Problems & Solutions Filter Problems by Issues: