My cheap Lexmark printer wasn’t working, so I replaced all the ink cartridges, checked its cable connections, checked the printer’s settings… all okay. As a last resort I went to the manufacturer’s support site and followed their instructions, to no avail.
Time to get serious: I unhooked the printer, taking it to the kitchen table with screwdriver in hand. Lifting its front cover, to get at the track the cartridge rides on, I saw… a pingpong ball.
“Daddy!”, my daughter said. “You found my pingpong ball! That’s where I put it!”