Canon Printer Error Code 2100 — What It Means & How to Fix It

What Does This Error Mean?

Canon error 2100 means the paper loaded in the printer does not match the paper size selected in the print settings. For example, you may have A4 paper loaded but the document is set to print on Letter size — or vice versa. The printer detects this mismatch and stops to prevent a wasted print. The fix is simply to match the paper in the tray to the size selected in your print settings.

Affected Models

Canon PIXMA MG3020
PIXMA MG3620
PIXMA TR4520
PIXMA TS3320
PIXMA MX490
Most Canon PIXMA all-in-one inkjet printers

Common Causes

The paper size in the print dialog does not match what is physically loaded in the tray
The paper size registered for the tray in the printer's settings has not been updated after changing paper
Printing from a phone or tablet app that defaulted to a different paper size than what is loaded
A document set to A4 size is being sent to a printer in a region where Letter is the default size
The paper size setting in the printer driver is different from the size set in the application

How to Fix It

Look at the printer's display or indicator lights. It will typically show what paper size it expected and what it found. Note the size it is requesting.

On Canon PIXMA models with an LCD screen, the display usually shows something like 'Loaded paper size: A4. Print job size: Letter.' This immediately tells you what needs to change.
Choose the easiest fix: either load the correct paper size into the tray, or change the paper size in your print settings to match what is loaded.

If you regularly use Letter paper, change the print settings. If you are printing a specific document that requires A4, load A4 paper instead.
If changing the paper in the tray: remove the old paper, load the correct size, and adjust the paper guides to fit. Then press the printer's OK or Resume button to tell it to re-check the tray.

After loading new paper, most Canon printers ask you to confirm the loaded paper size via the panel or app. Select the correct size.
If changing the print settings: go back to the print dialog on your computer, find the Paper Size setting, and change it to match the paper loaded. Resubmit the print job.

In most applications on Windows, the paper size is in File > Print > Printer Properties > Paper/Quality. On Mac, it is in File > Print > Paper Size.
Update the printer's registered paper size via the Canon PRINT app or printer's front panel. This ensures the printer always knows what size is loaded and reduces future 2100 errors.

Some Canon models allow you to set the default paper size for each tray permanently in the printer's settings menu. Setting this correctly prevents 2100 from appearing every time you print.

When to Call a Professional

Error 2100 is a settings mismatch — no hardware repair is needed. This is a free fix that takes about 1 minute. No technician is required.

Frequently Asked Questions

What is the difference between Letter and A4 paper?

Letter is the standard paper size in the United States and Canada — 8.5 x 11 inches. A4 is the standard in Europe, Asia, and most of the world — 210 x 297 mm (approximately 8.27 x 11.69 inches). They are very close in size but not identical. A printer set for one size will refuse to print on the other until the settings are corrected.

Why does my Canon printer keep showing 2100 when I print from my phone?

Many phone and tablet printing apps default to a different paper size depending on the app's regional settings. For example, an app set to the US region defaults to Letter, while one set to a European region defaults to A4. Check the paper size setting in the app before printing. Look for a Page Setup or Print Size option in the app's print menu.

Can I make my Canon printer ignore the paper size mismatch and print anyway?

On some Canon models, pressing the printer's Resume or OK button when error 2100 is displayed will force the print to proceed on whatever paper is loaded. The printed result may have content cut off at the edges or extra white space if the sizes differ significantly. This is useful for a one-off print but not a long-term solution.