While we're on subject I want to point out that cross contamination is not always caused by overfilling. Another effect called "nozzle migration" can also contaminate colors. Nozzle migration occurs when print head comes in contact with a non absorbing surface such as a plastic baggie or print head tape improperly applied. Or even a kitchen table.

The inks can migrate across print head by capillary action contaminating other color chambers. Before applying print head tape it is ESSENTIAL that print head is completely dry of any ink build up. Also do NOT store color cartridges in a plastic bag without some protection to print head. The best protection is a cartridge clip.

I learned this hard way. One time I had a load of virgin HP color cartridges that I sent off remanufacturer. I got whole shipment back because I tediously wrapped each one in plastic bags without anything protecting print heads. Every one had nozzle migration and they rejected them all. What a waste!

Actually effects of nozzle migration may go away by itself by using cartridge, If it's not too bad, that is. Printing out a color test pattern a few times can help a lot.

Some printers will be difficult and keep giving you error message, or will report wrong ink levels in ink monitor. In this case turn printer off and unplug it from wall. Wait about 20 - 30 minutes and try it again.

Also try rotating between 3 different cartridges when refilling. Some printers remember last two or three cartridges and can give you problems if you keep installing same refilled cartridge.

If you have an HP and printer prints but ink levels are not right you probably need to do "Tape Trick" Follow links below for type of cartridge you are refilling for correct procedure.

HP cartridges #'s 15, 45, 78 http://www.repeatotype.com/instructions/HPReset.pdf

HP cartridges #'s 56, 27 http://www.repeatotype.com/instructions/HP56Reset.pdf

HP cartridges #'s 57, 28 http://www.repeatotype.com/instructions/HP57Reset.pdf