Canon Canon imageCLASS LBP246dw 40 ppm Wireless Duplex Mono Laser Printer SIZE-MISMATCH Error Fix: Paper Size Mismatch

Error code SIZE-MISMATCH on the Canon Canon imageCLASS LBP246dw 40 ppm Wireless Duplex Mono Laser Printer means: Paper Size Mismatch. The paper size selected in the print job settings does not match the paper loaded in the tray, or the paper guides are set to a different size than the actual paper. Canon imageCLASS printers detect paper size using the position of the paper guides in the tray and/or optical sensors. Verify the paper tray guides are adjusted to exactly match the paper loaded. In the print driver, confirm the paper size setting matches (File > Print > Properties > Paper Size). If printing from USB or cloud, check the default paper size in the printer's menu settings. Common mismatches include Letter vs. A4, Legal vs. Letter, and envelope sizes. After correcting, press OK or Online on the printer to resume.

The most successful fix is "Inspect and Clean Paper Size Sensors and Replace Paper Tray if Faulty" (medium difficulty, ~30 minutes). Estimated DIY cost: $0-$10. HomeMD has 2 community-ranked fixes for this error.

This error is rated low severity. It is generally not urgent and can often be resolved with a simple DIY fix.

Yes — the top-ranked community fix ("Inspect and Clean Paper Size Sensors and Replace Paper Tray if Faulty") is rated medium difficulty and takes about 30 minutes. Tools needed: Phillips screwdriver, Lint-free cloth.

DIY cost: $0-$10. Professional repair typically costs $100-$180. Many homeowners save money by trying the top-ranked community fix first.

The Canon Canon imageCLASS LBP246dw 40 ppm Wireless Duplex Mono Laser Printer has 8 other known error codes, including: COVER-OPEN (Cover Open — Close Printer Cover), FUSER-ERROR (Fuser Error — Fuser Unit Malfunction), JAM-DUPLEX (Paper Jam in Duplex / Two-Sided Printing Path), JAM-INSIDE (Paper Jam Inside Printer / Near Toner Area), JAM-OUTPUT (Paper Jam in Output / Rear Area), and 3 more.

Error code SIZE-MISMATCH also appears on 3 other Canon models: Canon imageCLASS LBP632Cdw 22 ppm Wireless Duplex Color Laser Printer, Canon imageCLASS MF269dw II Wireless Duplex Mono Laser All-in-One Printer, Canon imageCLASS MF453dw 40 ppm Wireless Duplex Mono Laser All-in-One Printer. The fix may vary by model, so check each model's specific page for tailored repair steps.