Thanks for posting this question. I never imagined I'd be answering HP questions here but I am glad to do so. I served for 15 years at HP as a Tier 1, Tier 2 and Tier 3 Technician, with a specialty in Inkjet Printers (1999-2014). Basically, I'm an HP Printer Subject Matter Expert.
Frankly, I wish I had better news for you. It's time to replace your printer. If you have already turned it off and on, removed the power overnight and tried turning it on again, its likely that the printhead itself within the printer has failed - electrically.
Unfortunately HP doesn't design their consumer printers with repairability in mind.
I have, through multiple occurrences, determined that soaking the print head in a small pan of isopropyl alcohol will remove the clogging ink. I soak the print head for about 1 hour then dump the dirty liquid. Soak it again, then dip it multiple times allowing the liquid to drain. The liquid should be nearly clear. Dispose of the liquid and use paper towels to dry the print head. Tap it gently on the slot side to help get the liquid out of the interior.
"I have had an 8100 HP for 4+ years. 2 1/2 years ago I purchased new HP cartridges from Costco, Staples & Officedepot; none would work with my printer (I was using 950 & 951 cartridges). I contacted HP & they said that I needed to replace it with a new unit!!! That “po’d” me.
I then did extensive research in the web & found that the big-4-printer manufactures have placed software on their printer drivers to not read them! I then went to Costco with my empty cartridges & had them refill them (with new chips). I have been using these refilled cartridges for 2 years... recently it will not print due to “printhead: missing, failed or incompatible” error. This is clearly a new campaign to get us to buy new. Sooo sad. I believe you were caught by HP’s web; attempting to force you to repurchase another printer. Throwing away a perfectly good unit!
Any one out there with a work around to clear this error? I’ve unplugged, tried reset; from machine & from computer software, etc. I hope someone out there can help or send me somewhere to fix it."
