How to Clean HP Photosmart C4280 Inkjet Printer Nozzles

Turn on your HP Photosmart C4280 and the attached computer. Wait for the printer to finish its warm-up procedures.
Click on 'Start' on the computer's screen, then 'All Programs.' Find the folder labeled 'HP' and click on 'HP Solution Center.'
Select the 'Settings' tab in the Solution Center software. Hover the mouse over 'Printer Settings' so a drop-down menu appears, then click on 'Printer Toolbox' in the list.
Select the 'Device Services' tab and click on the button labeled 'Clean the Print Cartridges.' If after one cleaning you are not satisfied with the print quality, click on 'Clean Again' until you are pleased with the test page.