Hi @Kameshwar99
Welcome to the HP Support Community! We're here to help you get back up and running.
Thanks for explaining the issue—when your HP DeskJet Plus 4122 throws a “Paper size mismatch” error, even though you’ve loaded the correct paper, it’s usually due to a misalignment between the printer’s tray settings, driver configuration, and the application’s print settings.
Let’s walk through a structured fix to clear the error and get your pages printing smoothly.
Step-by-Step Fix for “Paper Size Mismatch” Error
1. Confirm Paper Size in Printer Tray
- Load Letter (8.5 x 11 inches) or A4 paper depending on your region.
- Adjust the paper width guides snugly against the stack—loose guides can trigger mismatch errors.
- Make sure the paper is flat, clean, and not curled or folded.
2. Set Paper Size in Printer Preferences
- On your PC:
- Go to Control Panel > Devices and Printers
- Right-click your HP DeskJet Plus 4122 → Printing Preferences
- Under the Paper/Quality or Advanced tab, set the paper size to match what’s in the tray (e.g., A4 or Letter)
- Click Apply and OK
3. Match Paper Size in Your Application
- In Word, PDF viewer, browser, or other app:
- Open the Print dialog
- Confirm the paper size matches your tray (A4 or Letter)
- Avoid “Fit to Page” or “Custom Size” unless you’ve loaded matching paper
4. Update Firmware and Drivers
- Visit: HP DeskJet Plus 4122 Drivers & Firmware
- Download and install:
- Latest firmware
- Full feature driver for Windows 11
- Restart your PC and printer after installation
5. Reset the Printer
- Turn off the printer
- Unplug the power cord for 60 seconds
- Plug it back in directly to a wall outlet (avoid surge protectors)
- Power on and try printing again
You’ve already done the hard part by identifying the error—let’s make sure your printer recognizes the paper and prints without interruptions. I’m here to assist.
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Take care, and have an amazing day!
Regards,
Hawks_Eye