Canon Printer Error Code E42 — What It Means & How to Fix It

What Does This Error Mean?

Error E42 means your Canon printer lost communication with your computer or network during a print job. The printer started receiving data but the connection timed out before the job was complete. This is usually a USB, Wi-Fi, or driver issue — not a hardware failure.

Affected Models

Canon PIXMA MG Series
Canon PIXMA MX Series
Canon imageCLASS MF Series
Canon MAXIFY MB Series
Canon PIXMA TR Series

Common Causes

The USB cable between the printer and computer is loose, damaged, or using a faulty port
The Wi-Fi connection dropped during a wireless print job, cutting off the data stream
The printer driver on the computer is outdated or corrupted and is sending incomplete data
The computer went to sleep or the USB port powered down during a long print job
A firewall or antivirus program on the computer is blocking communication with the printer

How to Fix It

Press the Stop/Reset button to clear the error. If using a USB cable, unplug it from both the printer and the computer, then reconnect it firmly.

Try a different USB port on your computer. Avoid USB hubs — connect the printer directly to a port on the computer.
If printing wirelessly, check that both the printer and computer are on the same Wi-Fi network. Restart your router if needed.

A 5 GHz Wi-Fi network can sometimes cause range issues. Try switching the printer to the 2.4 GHz network for more reliable connectivity.
On your computer, delete the pending print job from the print queue. Open Devices and Printers, right-click your Canon printer, and clear all documents.

A stuck print job in the queue can prevent new jobs from sending correctly.
Check your computer's power settings. Set the USB selective suspend setting to Disabled to stop Windows from powering down the USB port during printing.

Go to Control Panel > Power Options > Change Plan Settings > Change Advanced Power Settings > USB Settings.
Download and install the latest Canon printer driver from Canon's official website. Uninstall the old driver first.

Use Canon's IJ Network Device Setup Utility if setting up over Wi-Fi to ensure a clean network connection.

When to Call a Professional

Error E42 is almost always a connectivity or software issue you can resolve yourself. If the error appears on every job regardless of connection type, the printer's network module may have a hardware fault. Contact Canon support if software and cable fixes do not help.

Frequently Asked Questions

Why does E42 only happen on large print jobs?

Large jobs take longer to transfer, which gives more time for a connection issue to occur. Slow computers, busy networks, or USB hubs that lose power during sustained use are common culprits. Try printing large jobs in smaller batches to work around the issue while you diagnose the root cause.

Can a firewall cause Canon E42 errors?

Yes. Some antivirus programs and firewalls block the ports that Canon network printers use. Temporarily disable your firewall and try printing. If the error clears, add your Canon printer software to the firewall's allowed programs list.

Does E42 mean my printer needs to be replaced?

No. E42 is almost always a software or connection issue, not a hardware failure. Most E42 errors are resolved by updating the driver, fixing the USB connection, or improving Wi-Fi signal strength. Only consider hardware repair if the error persists after all software steps are completed.