Make sure you purchase the right ink cartridges for your specific printer. Cartridges are not compatible between different brands, and often not within the same brand. HP recommends that you use original HP ink cartridges. XL (Extra Large) cartridges cost more but do provide better value in the long run. They will be able to print at least double the pages of a regular cartridge. Our advice is that if you print often, go with XL. However, ink can dry up. So if you are not a frequent printer, go with the regular cartridges.
Ink level warnings and indicators provide estimates for planning purposes only. Consider getting replacement print cartridges when you receive a low-ink warning message. This avoids possible printing delays. You do not need to replace the print cartridges until print quality becomes unacceptable.
Use the ink-backup mode to operate the printer by using only one print cartridge. The ink-backup mode is initiated when a print cartridge is removed from the print cartridge carriage. During ink-backup mode, the printer can only print jobs from the computer. Printing in ink-backup mode slows the printer and affects the quality of printouts. When only a black print cartridge is installed, colors will print as grayscale. When only a tri-color print cartridge is installed, colors will print but black is grayed and is not a true black.
For your US HP Photosmart C4780 All-in-One Printer you need
HP 60 or HP 60XL cartridges.
For your European or UK HP Photosmart C4780 All-in-One Printer you need HP 300 or HP 300XL cartridges.
Try Amazon's ink selector tool to find compatible ink cartridges for your printer.
Replace the ink cartridges
2. Load plain white paper in the input tray.
7. Hold the cartridge by its sides with the nozzles toward the printer, and then insert the cartridge into its color-coded slot until it snaps into place. Make sure that the icon on the cartridge matches the icon on the slot. The tri-color cartridge is on the left side of the carriage. The black cartridge is on the right side of the carriage.
12. Close the lid, and then touch OK. The product scans the alignment page and completes the alignment process.
13. Remove alignment page and recycle or discard it.
The alignment page did not print?
If the printer did not print an alignment page, follow these steps to manually align the printer:
– Open HP Solution Center.
– In HP Solution Center, click Settings.
– In the Print Settings area, click Printer Toolbox. The Toolbox opens in a new window.
– In the Toolbox, click the Device Services tab, and then click Align the Print Cartridges.
– A dialog box displays. In the dialog box, click Print Page. The product prints an alignment page.
– Got to step 10.