OKI B432, MB472 and MB492: LOAD A4 / MEDIA MISMATCH 460–462 error — how to fix it

Last Updated on 11.08.2026 by DriverNew

An OKI B432, MB472 or MB492 may stop printing with a LOAD A4, SIZE MISMATCH, MEDIA MISMATCH message or error code 460, 461 or 462. Paper is often already loaded in the tray when this happens. The problem does not simply mean that the printer is out of paper: the print job settings do not match the paper size, media type or paper source registered in the printer.

To fix the error, you need to match four things: the page size in the application, the OKI driver settings, the paper actually loaded in the printer and the tray settings on the device control panel. Changing only one setting often provides a temporary solution, after which the message appears again when another document is printed.

Which models this guide applies to

The main steps apply to the following monochrome devices:

• OKI B412dn, B432dn, B432dnw and B512dn;
• OKI ES4132dn and ES5112dn;
• OKI MB472dn, MB472dnw, MB492dn and MB562dnw;
• OKI ES4172LP MFP, ES4192 MFP, ES5162 MFP and ES5162LP MFP.

The menu names differ between B-series printers and MB-series MFPs, so the control-panel configuration is described separately for each group.

What error codes 460, 461 and 462 mean

Why the error appears even though A4 paper is already loaded

For normal printing, the following settings must match:

1. Page size in the document. For example, A4 or Letter.
2. Print job settings in the driver. Size, Source, Type and Weight.
3. Paper in the tray. The actual sheet size and the position of the guides.
4. Tray settings on the device. Paper Size, Media Type and Media Weight.

The most common situation is that A4 paper is loaded in the main tray, while the document or application sends the print job as Letter. These sizes are similar, but they are not the same:

• A4: 210 × 297 mm;
• Letter: 216 × 279 mm.

The problem can also occur when the job requests Labels, Envelope, Letterhead or heavier paper while the tray is registered as Plain with a Medium weight. Selecting Auto as the paper source does not correct this mismatch: automatic tray selection only searches among trays that match the requested settings.

Step 1. Read the entire message on the display

1. Do not cancel the message immediately.
2. Write down the error code.
3. Write down the tray name: TRAY1, TRAY2 or MP TRAY.
4. Write down the requested size: for example, A4, LETTER, LEGAL 13 or CUSTOM.
5. Write down the paper type if it is shown: for example, PLAIN, LETTERHEAD, LABELS or ENVELOPE.

On B432 printers, the message may look like this:

LOAD A4/PLAIN AND PRESS ONLINE SWITCH
461: TRAY1 MEDIA MISMATCH

On the MB472 or MB492, the wording is usually shorter:

Tray Media Mismatch
Please install paper [MEDIA_TYPE] on TRAY1
Error code: 460

The exact wording is less important than three values: what is being requested, which tray is involved and which model you have.

Step 2. Check the paper and tray guides

1. Pull out the tray specified in the message.
2. Check the marking on the paper packaging. Do not try to distinguish A4 from Letter by sight alone.
3. Remove any sheets of a different size that may have been left accidentally underneath or on top of the stack.
4. Align the paper stack on a flat surface.
5. Move the side and rear guides exactly against the edges of the paper. They should touch the sheets without bending them.
6. Do not load paper above the maximum fill mark.
7. Push the tray fully back into the printer.

If you are using the MP Tray, unfold its supports, load the media and move the guides against the edges. Envelopes, labels and heavy paper should usually be fed through the MP Tray, after which you should specify the corresponding Paper Size, Media Type and Media Weight.

Step 3. Check the page size in the application

Application settings can override the saved driver settings. This is why the error may occur only with one document, browser or PDF file.

Microsoft Word

1. Open the document.
2. Go to the Layout or Page Layout tab.
3. Click Size.
4. Select the size that is actually loaded in the printer, for example A4.
5. Open File > Print.
6. Select the correct OKI print queue, not a duplicate.
7. Open Printer Properties and check the paper size and source again.

If the document was created for Letter paper, changing it to A4 may alter line breaks and the number of pages. Review the document before printing.

Adobe Acrobat or Acrobat Reader

1. Open the PDF and click Print.
2. Check the document page size in the print preview.
3. To print without scaling, select Actual size.
4. Open the OKI printer properties and select the same paper size.
5. If the PDF contains pages of different sizes, use automatic paper source selection based on PDF page size only when the device actually has multiple suitable trays configured.

The Fit option scales the content, but it does not by itself correct an incorrect paper size sent to the driver.

Browser

1. Press Ctrl + P.
2. Open More settings.
3. Find Paper size.
4. Select A4, Letter or another size that is actually loaded.
5. Open the system print dialog if the browser does not display the OKI driver properties.

If the browser constantly selects Letter on a computer where A4 is used, save A4 as the default paper size in the driver settings as described below.

Step 4. Match the size, source and media type in the OKI driver

Windows 11

1. Open Settings > Bluetooth & devices > Printers & scanners.
2. Select OKI B432, MB472, MB492 or your model.
3. Open Printing preferences.
4. If the option is not displayed, press Win + R, enter shell:PrintersFolder and press Enter.
5. Right-click the required print queue and select Printing preferences.

Windows 10

1. Open Settings > Devices > Printers & scanners.
2. Select the required OKI printer.
3. Click Manage.
4. Open Printing preferences.
5. If this option is unavailable, use shell:PrintersFolder as described in the Windows 11 instructions.

Settings on the Setup tab of the PCL6 driver

1. Open the Setup tab.
2. Select a Size that matches the document and the loaded paper.
3. For the first test, explicitly select Tray 1 instead of Auto.
4. For standard office paper, select Type: Plain and Weight: Medium.
5. Click Apply, then OK.
6. Return to the application, reopen the print dialog and check whether the application has overridden these settings.

If the Setup tab and the Type/Weight settings are missing, check the driver name. A Microsoft IPP Class Driver queue may not display proprietary OKI features. Install the PCL6 driver for your series and select the print queue created by that driver.

Step 5. Configure the tray on B412, B432, B512, ES4132 or ES5112

The printer control panel uses English abbreviations. Configure only the tray specified in the message.

1. Use the arrow buttons to open MENUS and press OK.
2. Select TRAY CONFIG and press OK.
3. Open TRAY1 CONFIG, TRAY2 CONFIG or MP TRAY CONFIG.
4. Open PAPERSIZE and select the size actually loaded.
5. Open MEDIATYPE and select the media type. For standard paper, select PLAIN.
6. Open MEDIAWEIGHT. For standard office paper, start with MEDIUM.
7. Press BACK until you exit the menu.
8. Press ONLINE to return the printer to the ready state.

The same section also contains PAPER FEED, AUTO TRAY SWITCH and TRAY SEQUENCE. These settings determine the primary tray and the automatic tray-switching order. Do not change them if the problem is caused only by an A4/Letter mismatch or an incorrect Media Type.

Step 6. Configure the tray on MB472, MB492, MB562 or a related ES MFP

1. Press the physical SETTING button.
2. Use the arrow buttons to select Paper Setup and press OK.
3. Select Tray 1, Tray 2 or MP Tray according to the message.
4. Open Paper Size and select the size actually loaded.
5. For custom-size paper, open Custom and specify its width and length.
6. Open Media Type. For standard paper, select Plain.
7. Open Media Weight. For standard office paper, start with Medium.
8. Press BACK to return to the main screen.
9. Send the test page again.

The Paper Setup section also contains Select Tray, Paper Feed, Auto Tray Switch and Tray Sequence. These settings do not replace the correct registration of the paper size and media type.

For MP Tray Usage, the default setting on this group of devices may be Do Not Use. If printing should use the MP Tray, select this source in the driver and enable its use in the device settings. If you do not need the MP Tray, do not enable it just to make the current message disappear.

Step 7. How to continue the current print job or cancel it correctly

If the display requests the correct paper

1. Load the specified size and media type into the specified tray.
2. On the B432, press ONLINE. The MB472 or MB492 usually resumes printing after detecting the tray; if a Start or OK command appears on the screen, confirm it.
3. Check the first printed sheet.

If the display requests the wrong paper

1. Select Cancel on the device or cancel the job from the Windows print queue.
2. Correct the page size in the application.
3. Correct Size, Source, Type and Weight in the printing properties.
4. Send the document again.

The ONLINE or Start button may allow the current job to print, but it does not correct the cause. The document may be printed at the wrong scale, on unsuitable media or from a different tray. Continue printing only after checking the request shown on the display.

Step 8. What to do if the printer constantly asks you to load paper into the MP Tray

1. Open the printing properties for the current job.
2. On the Setup tab, find Source.
3. If MP Tray or Manual Feed is selected but you are using the main tray, select Tray 1.
4. Check whether Labels, Envelope or a special paper weight has been selected.
5. If the source is set to Auto, temporarily select Tray 1 and print again.
6. Reopen the print dialog in the application: some applications save their own paper source for a specific document.

A message with code 490 means that the MP Tray is empty. A message with code 460 on the B series or 462 on the MB series means that the paper in the MP Tray does not match the print job. These are different problems.

Step 9. Configure a custom size without a Custom error

For custom-size paper, the same width and length values must be specified both in the driver and on the device control panel.

1. Measure the sheet in millimeters.
2. Determine the feed direction. Width is the dimension across the feed direction, while Length is the dimension along the feed direction.
3. Create a Custom Size in the driver using the exact dimensions.
4. Select the MP Tray or another tray that supports the required size.
5. On the B432, open MENUS > TRAY CONFIG > the required tray, select the custom size and specify X DIMENSION and Y DIMENSION.
6. On the MB472 or MB492, open SETTING > Paper Setup > the required tray > Custom and specify Width and Length.
7. Specify the same Media Type and Media Weight on the device and in the driver.
8. Print one page and check the orientation and margins.

For MB472/MB492/MB562 devices, the supported custom sizes depend on the tray:

If the entered size is not supported by the selected tray, the device will continue requesting different media or will not offer that size.

Step 10. What to do if all settings match but the error keeps returning

Check which print queue the document is being sent to

1. Open the Windows printer list.
2. Find all print queues with OKI in their names.
3. Open the queue containing the current print job.
4. Make sure the document is being sent through the official PCL6 driver rather than an old, WSD, IPP or duplicate queue.
5. Delete only unnecessary duplicate queues after successfully completing a test print from the correct queue.

Restore the default driver settings

1. Open Printing preferences for the required queue.
2. Find the command for restoring the default settings.
3. Set A4 or Letter according to the paper you use.
4. Select Plain, Medium and Tray 1.
5. Click Apply and OK.
6. Create a simple one-page document and perform a test print.

Install the PCL6 driver for your model group

If you are using a generic Windows print queue and the proprietary paper settings are unavailable, install the appropriate package:

• PCL6 driver for OKI B412/B432/B512 and related models;
• PCL6 driver for OKI MB472/MB492/MB562 and related models.

After installation, make sure the application has selected the new print queue. The old IPP queue may remain in the list and continue using incorrect settings.

Check the installed optional tray

If the error is related to Tray 2:

1. Open Printer properties, not just the printing preferences.
2. Find the Device Options tab or device settings.
3. Make sure the second tray is marked as installed.
4. If the Get Printer Information command is available, run it while the network connection is working.
5. Apply the settings and select Tray 2 again for the print job.

Clear a stuck print job that contains old settings

1. Cancel all jobs in the OKI print queue.
2. Turn the printer off and then on again if the cancelled job remains on the display.
3. Close the application from which you were printing.
4. Open the document again.
5. Set the paper size and source again and print one page.

Actions that usually do not fix the underlying cause

After correcting the settings, first print one simple page from the new OKI print queue, and then print the document that caused the problem. If the simple page prints correctly but the error occurs only with one file, return to the page and print settings in that application. If the message appears in every application, compare the driver settings and the menu settings for the specific tray again.