If your Canon printer cannot detect the paper size, or displays messages like “Paper size mismatch”, “Cannot detect paper size”, or Support Code 4102 / 4103, the issue is typically due to:
- Incorrect paper settings on the printer or computer
- Misaligned or improperly loaded paper
- Dirty sensors
- Mismatched tray configuration
- Software or firmware errors
Here’s how to resolve the issue step by step.
1. Check the Paper Loading and Alignment
Properly Load Paper into the Tray
- Use only supported sizes (e.g., A4, Letter, 4″x6″).
- Do not overload the tray or insert paper crookedly.
- Ensure the paper lies flat and is not curled or wrinkled.
Adjust the Paper Guides
- Slide the side and end paper guides to touch the edges of the paper gently.
- Guides that are too tight or too loose can cause detection errors.
2. Confirm Paper Size Settings on the Printer
On the printer’s control panel or touchscreen:
- Go to Settings > Paper Settings > Cassette / Rear Tray.
- Set the correct paper size (e.g., A4, LTR, 4×6) and paper type (e.g., plain, glossy).
- If prompted to register the paper information, select Yes.
Important: The printer uses these settings to detect and match what’s being sent from your computer.
3. Match Paper Settings on the Computer
Windows
- Open the Canon print dialog when printing.
- Go to Printer Properties > Page Setup tab.
- Set the same paper size and type as you selected on the printer.
- In the Main tab, check that the correct paper source is selected (e.g., Rear Tray or Cassette).
macOS
- In the Print dialog, click Show Details (if hidden).
- Set the Paper Size and Media Type to match the printer settings.
- Also check the selected tray/feed source under Paper Feed.
4. Disable Paper Size Detection (Optional)
If the printer constantly shows a mismatch despite correct settings, you can disable the paper mismatch warning.
On the Printer (if supported):
- Go to Settings > Device Settings > Print Settings > Detect Paper Settings
- Set Detect Paper Size or Mismatch Warning to Off
In the Canon Driver (Windows only):
- Go to Devices and Printers > Right-click Canon printer > Printing Preferences
- In the Maintenance or Custom Settings tab
- Uncheck Detect Paper Mismatch
Note: Disabling this removes the warning but won’t fix the underlying cause. Use only if necessary.
5. Clean the Paper Size Sensors (if applicable)
Dust or paper fragments may cover the paper width and length sensors, especially in:
- PIXMA and MAXIFY series
- Cassette or rear feed trays
Cleaning Steps:
- Turn off the printer and unplug it.
- Remove all paper from trays.
- Use a soft lint-free cloth to wipe around the paper feed area.
- For rollers and sensors, you can also run the “Roller Cleaning” from the printer’s maintenance menu.
6. Check for Firmware or Driver Updates
- Visit Canon’s official support site
- Enter your printer model
- Download and install the latest:
- Firmware
- Printer driver
- Utility software (e.g., Canon IJ Printer Assistant)
Updating firmware can fix known paper detection bugs.
7. Reset Printer Settings (if necessary)
If misconfigured settings persist:
Soft Reset
- Turn off the printer
- Unplug for 30 seconds
- Turn back on and retry
Factory Reset (if needed)
- Go to Settings > Device Settings > Reset Settings > Reset All
- This clears all user preferences (including Wi-Fi, paper settings, etc.)
8. Support Codes and What They Mean
| Code | Meaning | Solution |
|---|---|---|
| 4102 | Paper size mismatch | Check printer and driver paper size settings |
| 4103 | Cannot detect paper size | Check alignment, paper guides, and tray settings |
| 2110 | Paper size/type mismatch | Match paper size/type on device and PC |
9. When to Contact Canon Support
Contact Canon if:
- You’ve tried all steps and the printer still cannot detect paper size
- Sensors may be faulty or blocked internally
- The paper tray mechanism feels loose or doesn’t engage properly
- Firmware updates and resets do not fix the issue
Canon support can guide you through hardware checks or arrange service if needed.