Brother Printer Error Code 42 — What It Means & How to Fix It

What Does This Error Mean?

Brother error 42 means the scanner unit is locked or cannot move properly. The scanner is the glass bed used for copying and scanning documents. This is a moderate error — it is often caused by a shipping lock that is easy to remove.

Affected Models

Brother MFC-L2710DW
Brother MFC-L2750DW
Brother DCP-L2550DW
Brother MFC-J480DW
Brother MFC-J680DW

Common Causes

The scanner transport lock (a blue plastic tab) was not removed before first use
The printer was moved without locking the scanner, and the scanner head was knocked out of position
Debris or a fallen object is physically blocking the scanner carriage from moving
An internal scanner motor or belt has worn out or become disconnected
A firmware or software glitch caused the printer to incorrectly report the scanner as locked

How to Fix It

Turn off the printer and unplug it. Check underneath and around the scanner lid for a blue or green plastic shipping lock tab.

New printers ship with a plastic transport lock to protect the scanner during shipping. It must be removed before first use.
If you find the shipping lock, remove it completely. It will usually pull or slide out without tools.

Store the lock in case you need to transport the printer again in future.
Open the scanner lid and look at the glass bed. Check for any objects, paper, or debris sitting on the glass or in the scanner path area.

Even a small staple or paper clip on the glass can prevent the scanner head from moving.
Plug the printer back in and power it on. Listen for the scanner head making its startup movement — you should hear it slide from one side to the other.

If you hear grinding or no movement at all, there may be a mechanical problem inside the scanner unit.
If the scanner still shows error 42, try a full power cycle — hold the power button to force the printer off, unplug for 60 seconds, then plug back in and restart.

This can clear firmware-level glitches that cause false scanner lock errors.

When to Call a Professional

If removing the transport lock or clearing a physical obstruction does not fix error 42, the scanner mechanism itself may be damaged. Scanner unit repair or replacement typically costs $50 to $100. For older budget printers, buying a replacement unit is often more economical.

Frequently Asked Questions

What is the scanner transport lock on a Brother printer?

It is a small plastic tab installed at the factory to hold the scanner head in place during shipping. Without it, the scanner head could slide and get damaged during transport. It must be removed before you use the printer for the first time — the manual will show you where to find it.

Can I use my Brother printer for printing if the scanner shows error 42?

It depends on your model. On some Brother models, a scanner error will block all functions including printing. On others, only the scan and copy functions are blocked. Check your printer display for more details — it may indicate which functions are affected.

I already removed the transport lock but still get error 42. What now?

First, try a full power reset — unplug for 60 seconds and restart. Then open the scanner lid and carefully inspect the glass and scanner rail for any blockage. If nothing is visible and the error remains, the scanner motor or belt may need professional attention.