How to Troubleshoot an HP Officejet Pro L7780 All

1. Check the physical connections first to make sure the power cord is connected to a wall outlet and the USB cable is connected to your computer. Verify that a phone line is connected to the machine if you are attempting to fax. Power the printer off and then back on and attempt to print or copy again.
2. Restart your computer and attempt to use any of the L7780's features again. Navigate your web browser to the driver support web page for the HP Officejet Pro L7780 (see Resources).
3. Click on the option for your operating system. Click on the download link for the most recent driver software. Double-click the driver file once it has downloaded and follow the on-screen installation instructions.
4. Lift up the plastic auto document feeder on the top of the machine. Check underneath to see if there is a paper jam. Pull out any paper that is stuck inside. Rotate the blue plastic piece underneath the document feeder until you can see the paper rollers underneath.
5. Moisten a cloth with distilled water. Wipe off the paper rollers to clean any dust or ink residue. Rotate the blue plastic piece to its original position and then close the auto document feeder.
6. Lift up the entire top half of the L7780 and wait for the ink carriage to slide into view. Push up the plastic print head latch on the ink carriage and remove the ink cartridges. Look on the bottom of the ink cartridges to see if the gold print nozzles are damaged, which means the cartridge needs to be replaced.
7. Use the moist cloth to clean off the print heads inside the ink carriage. Put the ink cartridges back in and close the top half of the machine. Attempt to print a document again.
8. Open up the Start menu if the scanner is not working properly. Click on 'Programs' and then 'HP.' Select the 'Uninstall' option.
9. Insert the software disc that came with the L7780 into your computer's disc drive. Follow the installation instructions on the screen to re-install the scanner software. Attempt to scan a document again.
10. Contact HP support if the problem persists. Find out if your L7780 is still under warranty and if you are eligible for a replacement or repair job.