HP Envy 7640 Printing Problems
Make sure the HP Envy 7640 printer carriage moves freely. Open the carriage access door and check the movement. Replace the carriage if this doesn’t work. Check the HP Envy 7640 cartridge for leaks and replace it. Open the input and output trays, check for jammed paper bits using a flashlight, and remove them. Open the access door and inspect the area for paper bits stuck in the rollers and carriage. Take them out if present.