Epson Printer Warning Code W-21 — What It Means & How to Fix It

What it means

Warning W-21 is a general maintenance notice on Epson printers.
It can mean the printer needs a cleaning cycle, maintenance check, or a consumable item is near its limit.
This is a warning, not a shutdown — the printer can usually still print.

Affected Models

Epson WorkForce WF-3720
Epson WorkForce WF-3730
Epson Expression ET-3750
Epson EcoTank ET-4760
Epson WorkForce WF-7710

Common Causes

The printer's internal maintenance counter has reached a service milestone
A consumable item such as the maintenance box or ink pad is approaching its limit
The printer detected a print quality issue and is recommending a cleaning cycle
The printer has not been used for an extended period and is recommending maintenance
An ink cartridge requires attention — it may be low, empty, or unrecognized

How to Fix It

Check the printer's display panel for any additional details about what W-21 is referring to.

Some models display a sub-code or text message alongside W-21 to explain the specific issue.
Open Epson Status Monitor on your computer (right-click the Epson icon in the system tray).

Status Monitor gives more detailed information about the printer's current condition.
If the notice is about print quality, run a nozzle check and head cleaning from the maintenance menu.

On the printer: Setup > Maintenance > Head Cleaning.
If the notice is about ink levels, check all cartridges and replace any that are low.

Check the ink level display on the printer panel or in Epson Status Monitor.
After addressing the identified issue, press OK or Continue to dismiss the warning.

If the warning returns immediately, dig deeper into Epson Status Monitor for more clues.

When to Call a Professional

W-21 is a warning and rarely requires immediate professional service.
Check the printer's display or Epson Status Monitor for more details about what needs attention.
If the warning points to a failing component, contact Epson support for guidance.

Frequently Asked Questions

Can I keep printing if W-21 is showing?

Usually yes.
W-21 is a warning that allows you to continue printing.
Just press OK or the continue button on your printer's panel.
However, if the warning points to something important like a full waste ink pad, address it soon.

W-21 appeared after I reinstalled my printer driver. Is that related?

Possibly.
Driver reinstallation sometimes causes the printer to re-evaluate its maintenance counters.
Also, if the reinstallation included a firmware update, new maintenance thresholds may have been applied.
Check the printer's maintenance status in Epson Status Monitor.

How do I stop W-21 from appearing after every print job?

Find and fix the underlying issue the warning is pointing to.
Once the root cause — such as low ink, waste pad level, or print quality — is resolved, the warning will stop.
Suppressing warnings without fixing the cause can lead to bigger problems later.