HP Printer Problems and How to Fix Them

Not every HP printer problem is a jam, an offline printer, or a bad driver. Sometimes it's an OfficeJet that says "Printer Failure" every time you switch it on, a code like 0x6100004a, a scanner that won't start, a fax that never arrives, or a printer that won't power on at all.

This page covers those leftovers. For each one, you'll find what the message points to, the steps HP gives for it in the order HP gives them, and the point where more troubleshooting at home stops being worth your time.

If your problem has its own guide (offline, paper jam, Wi-Fi, numbered error codes), you'll find links to all of our HP guides at the bottom of this page.

Find Your Problem

Jump to the section that matches what you're seeing:

• "Printer Failure 0x6100004a" after a paper jam message, reported most on the OfficeJet Pro 6830, 6968, and 6978
• "Printer Failure. There is a problem with the printer or ink system." on an OfficeJet 6100, 6600, 6700, or a related OfficeJet model
• "Printhead Problem," "Missing or Failed Printhead," or "Incompatible Printhead"
• "Used, Refilled, or Counterfeit Cartridge"
• "Scanner Failure," or the HP app says scanning is unavailable
• The document feeder won't take your originals, or pulls in several at once
• "Out of Paper" when the tray is full
• The printer won't turn on, or shuts itself off
• Grinding or other loud noises
• Pages of random characters or symbols
• Faxes won't send or come in
• Printing from an iPhone, iPad, or Android phone

Before You Start

Three things make every fix on this page go faster.

Write down the message, word for word. HP has separate support documents for messages that sound almost the same. On the same OfficeJet, "Printer Failure" and "Print System Problem" lead to different steps, and a code that starts with 0x can change what you try first.

Learn HP's reset. Almost every HP document on this page includes the same reset, and it does more than switching the printer off and on:

1. Press the power button to turn the printer off. If it won't turn off, pull the power cord out of the back of the printer.
2. Unplug the cord from the wall, power strip, or surge protector.
3. Wait 60 seconds.
4. Plug the cord straight into a wall outlet, then back into the printer.
5. Turn the printer on.

Whenever a section below says "reset the printer," this is what it means.

Use the HP app, not HP Smart. HP has replaced HP Smart with the HP app, and once the HP app is available for your device, HP Smart can't be reinstalled. The app's Diagnose & Fix tool takes over from HP Print and Scan Doctor, which HP retired in May 2025. You'll also use the app for firmware updates: click your printer, open Advanced Settings, and look for Printer Update. Never turn the printer off while an update is installing. HP warns that it can permanently damage the printer.

HP Printer Error 0x6100004a

"Printer Failure 0x6100004a" tends to show up right after a paper jam message, often for a jam you can't find. HP's document on it covers its OfficeJet all-in-one printers, and on HP's support forum the reports come mostly from owners of the OfficeJet Pro 6830, 6968, and 6978. Some screens add a second line: "There is a problem with the printer or ink system. Turn the printer OFF, then on."

If turning it off and on hasn't cleared it, HP's fix comes in two parts.

Part 1: Clear the paper path

1. Open the cartridge access door.
2. If your model has a removable paper path cover inside, take it out. Remove any torn paper, labels, or other bits you find. A flashlight helps.
3. Push the paper path cover back in all the way. If it sits even a little high, the access door won't close properly.
4. Close the door until it's fully seated.

Look closely, because tiny pieces count. In one thread on HP's forum, an OfficeJet Pro 6968 owner found a scrap of paper about a quarter inch square sitting on the silver rail at the very back of the cartridge area.

Part 2: Restart the printer without its cartridges

1. Turn the printer off with the power button, then open the cartridge access door.
2. Turn the printer on and wait for the carriage (the part that holds the cartridges) to move.
3. With the printer still on, unplug the power cord.
4. Take the ink cartridges out and set them aside. You may need to slide the carriage over by hand to reach them.
5. Leave the door open, plug the printer back in, turn it on, and let it finish starting up.
6. Once the carriage returns to the center and the error is gone, put the cartridges back in.

HP says you can repeat Part 2 up to three times. Work quickly while the cartridges are out. HP's printhead document warns against leaving cartridges out of the printer for more than 30 minutes.

Worth a try if it keeps coming back: an HP Support moderator on HP's forum also suggests cleaning the encoder strip. That's the clear plastic strip running behind the carriage that tells the printer where the carriage is. Wipe it gently with a soft, lint-free cloth lightly dampened with water, and be careful not to knock it out of place.

When to stop: if the error survives three rounds, or the carriage won't move at all with nothing in its way, HP's next step is service. Look up your coverage on HP's Warranty Check page first. Repair fees can apply once the printer is out of warranty, so on an older OfficeJet, get a quote and compare it with the price of a new printer before you agree to anything.

"Printer Failure" on the HP OfficeJet 6100, 6600, and 6700

The full message reads "Printer Failure. There is a problem with the printer or ink system," and the printer won't print. The 6100, 6600, and 6700 are the models most people search for, but HP's document lists more than 30 OfficeJet and OfficeJet Pro models that show the same message. They include the 276dw, the OfficeJet Pro 6960 and 6970 series, the 7110, 7510, 7512, 7610, and 7612, and the 8100 and 8600 to 8660 models.

If your message includes the code 0x6100004a, start with the section above instead.

Otherwise, work through these in order and try printing after each one.

1. Clear the carriage path.
With the printer on, unplug the power cord from the back. Open the access door and look for crumpled paper or a label that came loose, and take out anything you find. Then push the carriage by hand to each side. It should slide freely. Close the door, plug the printer back in, and turn it on.

2. Reset the printer.
Use HP's 60-second reset from the top of this page.

3. Check the cartridges for leaks.
HP's document for the related "Print System Problem" and "Problem with Ink System" messages also covers these three models, and it starts here. Wait for the carriage to stop, take out one cartridge at a time, and look for leaking ink. Don't put a leaking cartridge back in. Return the good ones to their slots.

4. Reseat the printhead.
The printhead sits in the carriage, underneath the cartridges. If the carriage has a latch:

1. With the printer on, unplug the power cord.
2. Lift the latch, raise the printhead slightly, and lower it back into the carriage.
3. Wiggle it left and right, then lower the latch until it stops.
4. Close the door and plug the printer back in.

If the message is still there, HP says to repeat the reseat up to three times.

5. Try genuine HP cartridges if you've been using others.
This isn't one of HP's steps, but it's worth knowing. On HP's forum, an OfficeJet 6600 owner got "Printer Failure" right after putting in a new cyan cartridge, and a reset didn't help. Swapping the non-HP cartridges for genuine HP ones cleared it.

If none of that works, HP's next step is a new printhead or service. There's a catch with these three models, though. They use HP 932 and 933 cartridges, and HP's current printhead document doesn't list a replacement printhead for that cartridge group. In practice, that leaves HP service or an independent repair shop. On a printer this old, price a replacement printer at the same time so you can compare.

HP Printhead Errors: "Printhead Problem," "Missing or Failed Printhead," and More

HP treats these messages as one problem: Printhead Problem, Printhead Failure, Printhead Missing, Missing or Failed Printhead, Printhead Missing or Damaged, Printhead Appears to be Missing or Damaged, Printhead is Missing, Not Detected, or Not Properly Installed, and Incompatible Printhead. Each one means the printer can't find, or can't talk to, a working printhead.

These steps aren't for Smart Tank or other ink tank printers. HP has separate printhead documents for those.

First, find out whether your printhead comes out. Open the cartridge access door and wait for the carriage to stop. Look for a latch on the carriage. If there's no latch, the printhead isn't something you can replace, and HP's answer is repair or replacement. If there is a latch, find your cartridge number below. It's printed on the cartridge label.

If your printer uses HP 178, 364, 564, 655, 862, 902 to 910, 912, 914 to 920, 934, or 935 cartridges

HP has you clean the printhead's electrical contacts. Have a lint-free cloth and distilled or bottled water ready before you start.

1. Push in the tab on each cartridge and lift it out. Don't leave the cartridges out for more than 30 minutes. HP says that can damage both the printer and the cartridges.
2. Lift the carriage latch until it stops. Hold the printhead by its sides and lift it out.
3. Lightly dampen the cloth and wipe the copper-colored contacts from bottom to top until no more ink comes off. Stop at the edge where the contacts meet the ink nozzles. Don't touch the contacts with your fingers or set them down on anything.
4. Using a clean spot on the cloth, wipe away ink and debris along that edge. Then wipe the ramps on both sides of the nozzles, always moving away from the nozzles.
5. Go over each of those areas again with a clean, dry, lint-free cloth.
6. Wipe the contacts inside the carriage from top to bottom until the cloth comes away clean, then dry them.
7. Slide the printhead back in and lower the latch. Snap each cartridge into its color slot so none of them sticks up, then close the door.

Still seeing the error? HP sells the replacement printhead for this group: part CN643A if your printer takes four ink cartridges, or CN642A if it takes five. A defective printhead may still be under warranty, so check that before you buy one. If a new printhead doesn't fix it, reset the printer. If the error is still there after that, the printer needs service.

If your printer uses HP 932, 933, 936 to 938, 950 to 959, or 962 to 969 cartridges

HP doesn't have you clean these printheads. Its order is:

1. Update the printer firmware.
2. Reset the printer.
3. Reseat the printhead with the lift, lower, and wiggle steps from the OfficeJet section above. Repeat up to three times.

If the error won't clear, HP's printhead document lists these replacement parts: 4S6Z3A for HP 936 to 938 cartridges, CR322A for HP 950 and 951 cartridges in the Americas, M0H91A for HP 952 to 959, and 3JB16A for HP 962 to 969. As mentioned above, there's no listing for printers that use HP 932 and 933.

Older OfficeJet Pro models that take HP 88 or HP 940 cartridges, such as the K5400, 8000, and 8500, use two separate printheads and have their own steps in the same HP document.

"Used, Refilled, or Counterfeit Cartridge" Message

You might see "Used, Refilled, or Counterfeit ink cartridge Detected" or "Counterfeit ink cartridge Advisory," and the printer stops printing. HP says the message means the printer thinks a refilled or counterfeit cartridge is installed. HP also says it can appear with genuine HP cartridges that are empty or nearly empty, so don't assume you were sold a fake.

If your cartridges are genuine HP: choose No, OK, or Continue on the printer. If the job prints, you're done. You may have to dismiss the message each time you print until that cartridge runs out.

If the message won't let you print:

1. Reset the printer.
2. Replace the cartridge named in the message. If your printer is enrolled in Instant Ink, replacements are part of your subscription, so use a spare Instant Ink cartridge or contact Instant Ink support for one. If it isn't enrolled, buy the right cartridge for your model.
3. Close the door and follow any prompts to align the printer.

Bought cartridges sold as new HP stock and still think they might be fake? HP's Anti-Counterfeiting and Fraud Program page explains how to check and report them. Hang on to the box and your receipt.

Seeing a different cartridge message, like "Incompatible," "Protected," "Non-HP Chip," or a cartridge problem on an HP+ printer? Our HP printer error codes and messages guide covers those.

HP Scanner Not Working: "Scanner Failure" and "Scanning Unavailable"

These two look alike but come from different places. One is a hardware message on the printer's screen. The other is the HP app losing touch with the printer.

"Scanner Failure" on the printer's screen

The message usually reads "Scanner failure. Unable to scan, copy, or send a fax" or "Scanner System Failure." HP says it comes from the scanner hardware or its power, like a scanner bar that's stuck or can't calibrate, a scanner lamp that isn't warming up enough, or an electrical problem. It isn't caused by Wi-Fi or USB. HP's steps:

1. Reset the printer.
2. Watch the scanner bar. Take everything off the glass, lift the lid slightly, and press Copy. The bar under the glass should light up and travel the full length of the glass. If it doesn't light up or doesn't move, HP says the printer needs service, and you can skip the rest of this list.
3. Reinstall the printer software. Remove the printer from Printers & scanners in Windows (or Printers & Scanners on a Mac), then set it up again in the HP app.
4. Restore factory defaults. Type the printer's IP address into a web browser to open its Embedded Web Server. Go to the Settings or System tab and choose Restore Factory Defaults. If it asks for a PIN, you'll find it on a label inside the cartridge access area or behind a printer door. (On LaserJets, the username is "admin.") The printer restarts in about 20 seconds. This also wipes its Wi-Fi settings, so you'll need to reconnect it.
5. Service the printer if the message is still there.

"Printer Not Available" or "Scanning Is Currently Unavailable" in the HP app

This one is a connection problem between your computer or phone and the printer.

If the printer is on Wi-Fi or Ethernet:

1. Turn off the printer and your computer or phone, and restart your router. Then turn the printer back on, followed by your computer or phone.
2. Make sure your computer or phone is on the same network name as the printer. On the printer, a solid blue Wireless light means it's connected.
3. Check the status shown next to the printer in the HP app. If it says Printer Not Connected, Unavailable, or Printer Offline, our HP printer offline guide is the place to go next.
4. Run Diagnose & Fix in the HP app: click your printer, click Diagnose and Fix, then click Start. Leave the app open until it finishes.
5. Remove the printer from the app (click the printer, scroll to the bottom, and click Remove from app), then add it again.

If the printer is connected by USB:

1. Make sure Windows updates aren't paused. HP says fixes for scanning sometimes arrive through Windows Update.
2. Reset the USB connection. Unplug the USB cable and close the HP app. In Control Panel, open View devices and printers, select your printer, and click Remove device. Do the same for any other copies with the same name. Open Task Manager and end any HP or HP Smart tasks. Then plug the cable back in and wait a few minutes for the printer to reappear in Printers & scanners. On a Mac, remove the printer from Printers & Scanners, reconnect the cable, and check that the Scan tab or Open Scanner button shows up.
3. Try scanning with a different program. On Windows, download HP Easy Start from 123.hp.com/setup, install the full feature drivers, and scan with HP Scan. On a Mac, open Image Capture.

Did scanning stop right after a Windows update, or can your printer no longer save scans to a folder on your PC? Our HP printer issue after Windows update guide covers both.

Document Feeder Won't Pull Pages In, or Grabs Several at Once

When the automatic document feeder (ADF) on top of your all-in-one won't take your originals, or pulls in a bunch at once, you might also see "Load original" or "Document feeder mispick." HP's fix is cleaning the feeder's rollers and separator pad.

1. Take your originals out of the feeder. Turn the printer off and unplug it.
2. Open the ADF cover and find the paper pick rollers and the separator pad.
3. Lightly dampen a clean, lint-free cloth with distilled or filtered water, and squeeze out the extra.
4. Wipe the rollers and the separator pad.
5. Leave the cover open for two minutes so everything can dry. Close it, plug the printer in, and turn it on.

If it still misfeeds, reset the printer. After that, HP's next step is service. HP recommends cleaning the feeder regularly to help prevent jams and quality problems.

Printer Says "Out of Paper" When the Tray Is Full

An "Out of Paper" or "Load Paper" message with paper sitting right there usually means the rollers aren't catching the top sheet.

Reload the paper the way HP describes:

1. Take the whole stack out.
2. Pull out any sheets that are bent, wrinkled, or torn.
3. Check the tray for anything that could keep the paper from reaching the rollers.
4. Tap the stack so it's even on all sides, load it, and close or push in the tray.
5. Make sure the paper size selected on the printer or in your print settings matches what you loaded.

Clean the pick rollers:

1. Turn the printer off, wait until it's quiet, and unplug it. Take the paper out.
2. Find the pick rollers with a flashlight. Depending on the model, they're down inside a top-loading input tray, under the cartridges, above the input tray, or underneath the printer when the paper tray is at the bottom. For that last type, HP has you pull out the tray and set the printer on its side or back to reach the gray rollers. Don't tip a Smart Tank or other ink tank printer, though, since ink can spill.
3. Dampen a cotton swab with water and squeeze it nearly dry.
4. Clean the rollers, turning them with your fingers so you get all the way around.
5. Let them dry for two minutes. Set the printer upright if you tipped it, plug it in, and turn it on.

Still not picking up paper? Reset the printer, and if that doesn't do it, the printer needs service. If paper feeds but then jams, our HP printer paper jam guide picks up from there.

HP Printer Won't Turn On or Keeps Turning Itself Off

No lights, no sound, nothing

First, check how your printer gets its power. If the cord runs straight from the wall to the printer, the power supply is built in. If there's a separate power brick along the cord, it's external.

1. Unplug it for a full minute. Disconnect the cord from the printer and from the wall, power strip, or surge protector. After at least 60 seconds, plug it back into the printer and straight into a wall outlet.
2. Press and release the power button. Don't hold it down. HP notes that holding it too long can make the printer turn on and then shut right back off. If nothing happens, wait 10 seconds and press it again. If your printer has a power switch instead, switch it off and then on.
3. Try a different outlet, then a different power cord with the same connector if you have one.
4. Check the power brick, if your printer has one. The voltage and amperage printed on it should match what's printed on the printer. Most bricks also have a small light. If the light is on and the printer still won't start, HP says the printer needs service. If the light is off, try another cord, and if that doesn't help, replace the power module.
5. Built-in power supply: if a different outlet and cord don't help, HP's next step is a new power module from the HP Parts Store, or service.

It turns off on its own

Before you assume something is broken, check the power settings. HP printers are designed to switch themselves off after sitting idle, to save power. Press the power button and the printer comes right back.

• On printers with a display, look for Auto Power Off or Schedule On and Off in the Setup menu.
• In the HP app, open your printer's Advanced Settings, go to the Settings tab, and click Power Management. Enter the printer PIN if it asks.

On some models, the auto-off timing is preset and can't be changed.

If the printer shuts down in the middle of a job or won't wake up from sleep, HP's steps are to reset it, update the firmware, plug the USB cable straight into the computer instead of through a hub, and take out any memory cards or USB drives. If it still cuts out, the power module (or the battery, on a mobile printer) needs replacing, or the printer needs service.

Grinding, Clicking, or Other Loud Noises

Some noise is normal. HP says inkjet printers make sounds while they work, especially when they start up. A loud, metallic, or grinding sound is a different story. HP ties it to a paper jam, a stalled carriage, or another problem.

1. Check every place paper can hide. Turn the printer off and unplug it before you reach inside. Then check the document feeder and under the scanner lid, the rear access door, under the paper path cover, the bottom cleanout door if your model has one, and the input and output trays with a flashlight. Pull paper straight out with both hands. HP says not to use tweezers or pliers.
2. Make sure the carriage moves freely. Turn the printer on, open the carriage door, wait until it goes quiet, and unplug it. Remove any paper near the carriage. Take out the cartridges or printhead, look them over for damage, and wipe inside the carriage with a lint-free cloth. Put everything back, then slide the carriage from one side to the other and back. It should travel the full width without catching.
3. Reset the printer and update its firmware.
4. Check that the printer is level. HP specifically recommends a flat, level surface to prevent printing problems and noise. A bubble level will tell you in seconds.
5. Clean the paper feed rollers. Dirty rollers can be noisy. The cleaning steps are in the "Out of Paper" section above.

If the noise is still there, HP's next step is service.

Pages of Random Characters, Symbols, or Gibberish

When an HP printer turns out pages of strange letters and numbers, the cause is usually the connection between your computer and the printer, or the program you printed from.

On a Windows computer (any HP printer):

1. Cancel the job. Open Printers & scanners, select your printer, click Open queue, then right-click the job and cancel it. If it won't leave, see our HP printer job stuck in queue guide.
2. Reset the printer.
3. Print from a different program. If Word prints fine and only your photo app produces junk, the problem is that app, not the printer.
4. Connect directly with USB. Turn off the printer's wireless, unplug any network or USB cables, restart the printer, and connect a USB cable straight from the printer to the computer.
5. If it still prints garbage, the printer needs service.

Extra pages of unwanted text right after you plug in a USB cable? HP's workaround is to unplug the cable, then download HP Easy Start or the full feature software for your model from HP's Software and Driver Downloads page and choose Full Software and Drivers during setup. After that, remove the printer from Printers & scanners, turn it on, plug the USB cable back in, and let Windows add it again.

Pages that start with "POST /ipp/print" after a Windows update were a known Windows bug in 2025. Our HP printer issue after Windows update guide covers it.

On a LaserJet, HP adds a few checks:

• Print a test page from the printer itself, either by holding the Information button for about three seconds or from the Reports menu. If the test page is garbled too, take out each toner cartridge, pull off any sealing tape, check it for leaks or cracks, and put it back. Don't touch the green roller (the imaging drum).
• If the test page looks normal, the problem is between the computer and the printer. Set your printer as the Windows default (turn off "Let Windows manage my default printer" first), plug the printer straight into a wall outlet, try a new USB cable, and restart the computer.
• Look at where the printer sits. HP says drafts, high heat, very high or very low humidity, a closed cabinet, and blocked top vents can all hurt print quality.

HP Fax Problems: Can't Send, Can't Receive, or Poor Quality

Start with two tests.

1. Print a fax test report. On the printer, look for Run Fax Test or Fax Test Report in the Fax or Setup menu. It checks the printer, the phone line connection, and your fax settings, and tells you which check failed.
2. Send a fax to HP's free Fax Test Service at 1-888-473-2963 (1-888-HPFaxme). If your fax is working, it faxes you back within 5 to 7 minutes. The return fax only reaches you if the number in your printer's fax header matches your real fax number.

If faxes won't send

• Redial by hand, with any outside line code (like 9) and the area code. If you use speed dial, check that the saved number is right.
• Lower the fax speed to Slow or Standard.
• Turn on Error Correction Mode. Faxes take longer, but more of them get through.
• Send in black and white. The machine on the other end may not accept color.
• Check the dialing type. Most phone lines use tone dialing.

If faxes won't come in

• Turn on Auto Answer. Without it, you have to answer every fax call yourself.
• Sharing the line with an answering machine? Set the printer's Rings to Answer higher than the answering machine's. Keep your greeting to 10 seconds or less, cut the background noise, and leave about 5 seconds of silence at the end so the printer can hear the fax tones.
• Set the ring type. Use All Rings on a dedicated fax line, or Distinctive Ring if your phone company gave your fax number its own ring pattern.
• Watch for phone line extras. Voicemail, call waiting, anonymous call rejection, and privacy manager services can all block incoming faxes. Ask your phone company to turn them off for the fax line.

Check the phone line (for sending and receiving)

• The cord from the wall jack goes into the printer's 1-LINE port. A phone or answering machine goes into 2-EXT.
• Use the two-wire phone cord that came with the printer. Four-wire cords cause trouble, and a short, good-quality cord works better than a long, cheap one.
• Plug a regular phone into the wall jack and make a call. No dial tone usually means another device is holding the line open. Static points to interference from motors, fans, TVs, or coax cables, or to a line problem your phone company needs to fix.
• Unplug other devices sharing the line, like modems or extra phones, while you test.
• On DSL, connect the printer through a DSL microfilter. On VoIP, plug the printer's phone cord into the VoIP gateway, lower the fax speed, turn on Error Correction Mode, and hold off on streaming or gaming while you fax.

Messages you might see while faxing

• Phone Off Hook: a phone on the line is off the hook, or the line is still open. Check the line, then reset the printer.
• Fax Log or Fax Memory Is Full: use Clear Fax Logs in the Fax or Setup menu. Print any stored faxes first if you need them.
• Scanner Failure: this stops faxing too. See the scanner section above.
• A number code (3, 12, or 15 digits): search HP's support site for it. Turning on Fax Error Reports makes the printer print a report any time a fax fails.

Faxes come out streaky or blurry

Print a regular document first. If that looks bad too, it's a printing problem, not a fax problem.

• Only the faxes you send look bad: turn the printer off and clean the scanner glass, the narrow glass strip if your model has one, and the white backing under the lid. Use a lint-free cloth with glass cleaner or distilled water, and spray the cloth, not the glass. If you have a document feeder, wipe its rollers and pad too. Let everything dry before you turn the printer back on.
• Only the faxes you receive look bad: lower the fax speed, turn on Error Correction Mode, and update the printer's firmware.

Printing From an iPhone, iPad, or Android Phone

You don't need an extra app just to print from your phone. Apple and Android both have printing built in, and HP's tools fill in the gaps.

iPhone and iPad

HP printers work with Apple AirPrint, which is part of iOS.

1. Connect your iPhone or iPad to the same Wi-Fi network as the printer.
2. Open what you want to print, tap the Share icon (or the menu icon), and choose Print.
3. Pick your printer, choose copies and pages, and tap Print.

"No AirPrint Printers Found"? Check that the printer's wireless light is on and not blinking, move your phone and the printer closer to the router, and restart the printer. If web pages are loading slowly too, unplug the router for 15 seconds and plug it back in. If the printer still doesn't show up, open its Embedded Web Server (type the printer's IP address into a browser) and make sure AirPrint is turned on in the Network settings.

No Wi-Fi network at all? Use Wi-Fi Direct. Find the printer's Wi-Fi Direct name and password (touch the Wi-Fi Direct icon on a touchscreen model, or print an information report on other models). On your phone, join the network whose name starts with DIRECT, then print with AirPrint as usual.

Android phones and tablets

HP gives you two options:

• HP Print Service Plugin, free on Google Play. HP says it works with most HP printers released after 2004, and on Android 7 or later it turns on by itself once it's installed.
• Mopria Print Service. HP says most HP printers released after 2014 support it. HP's instructions only have you install the Mopria app on Android 7 or earlier.

To print, open the item, tap the menu icon, tap Print, and pick your printer.

• Printer not showing up? Add it by IP address. In the HP plugin, tap All printers, then Add printer, then HP Print Service, then On a Wi-Fi Network. In Mopria, tap the plus sign. You'll find the printer's IP address on its control panel or on an information page it prints.
• Jobs failing or stuck? Clear Android's print spooler. Open Settings, then Apps, show system apps, tap Print Spooler, then Storage, and clear both the cache and the data.
• Router with two bands? Not every HP printer supports 5 GHz. If your router gives each band its own network name, put the printer on the 2.4 GHz one.
• LaserJet printing PDFs or online forms as unreadable junk? In the HP Print Service Plugin, tap the menu, then Print settings, then Advanced Settings, and turn on Android Print Rendering.

To scan from your phone, check ink levels, or change printer settings, you'll want the HP app. HP says it supports most wireless printers made in 2014 or later.

When It's Time for Service

Stop troubleshooting and look at your repair options if you run into any of these:

• 0x6100004a is still there after three rounds of HP's cartridges-out restart.
• The carriage won't move by hand, and nothing is blocking it.
• "Printer Failure" or a printhead error survives three printhead reseats, or a new printhead.
• The scanner bar doesn't light up or move when you press Copy.
• The power brick's light is on, but the printer stays dead.
• The grinding doesn't stop, even with every door checked and the printer sitting level.

Start with HP's Warranty Check page and your printer's serial number. Repair fees can apply once a printer is out of warranty. For a rundown of repair options, and how to spot fake "HP support" callers, see the repair section of our HP printer error codes and messages guide.

How to Avoid These Problems

A few habits from HP's own documents head off a lot of what's on this page:

• Turn the printer off with its power button, and wait for the power light to go out before you unplug it. HP's OfficeJet 6100 user guide warns that shutting it off the wrong way can leave the carriage out of position and cause printhead and print quality problems. Save the unplug-while-it's-on method for HP's reset.
• Never turn the printer off with cartridges missing, and don't leave cartridges out for more than 30 minutes.
• Plug the printer straight into a wall outlet rather than a power strip or surge protector. HP recommends this all through its troubleshooting steps.
• Keep the firmware up to date, and never power off during an update.
• Keep the printer on a flat, level surface.
• Clean the document feeder's rollers and pad from time to time, as HP recommends for all-in-ones with an ADF.