@Joe Arseneau wrote:
When one or more of the colors on an inkjet printer stops printing, there may be a blockage on the cartridge's print head or at the point where the cartridge connects to the printer's ink tubes.
These blockages are caused by dry ink; you can usually clear off the blockages by running the printer's self-cleaning utility. To clear more severe blockages, you can manually clean the ink cartridges and lines by wiping them with isopropyl alcohol or soaking the print head in water.
If nothing works, you will need to replace the ink cartridge or have the printer serviced.