Firmware update tool for OKI MB451 with very old firmware (2011?)

[habdk]

Hi,
I was recently gifted a big box containing a "brand new" OKI MB451 MFP. Well, new as in unopened box, I believe the MFP is from 2011. I have it setup on my network and it prints/scans/copies fine. I feel a strong urge to update the firmware. The current official Firmware Update Tool from OKI doesn't recognize the printer - I tried with both network and USB cabled directly to both a Mac, a Windows 7 PC, Windows 11 PC and even tried the iOS version on iPhone. It always comes up as "Device not found" - so no way to update the firmware through that tool.
I read that someone got it to work by using a USB stick and a special tool provided by an OKI technician. I contact OKI support several times, and even got referred to a local OKI service-center, but it seems they didn't know about this tool, friendly as they were.
So - does anyone here know about such tool to bring it into the current decade? :-)
Here are the current versions according to the web GUI:

Version Information
CU 01.28
PU 00.06.08
Network Firmware 01.14
Web Remote 01.10
Web Language 01.10


System
CU Version 01.28
PU Version 00.06.08
Scanner Version 01.24
Total Memory 256 MB
Flash Memory 16 MB [F64]

I appreciate any input, thanks.

[boutn]

here is your firmware:

https://www.oki.com/uk/printing/support/firmware/?tab=firmware&productCategory=mono-multifunction&sku=01327201&type=firmware

you can upload it to the printer using 'OKI LPR UTILITY'

just make sure SNMP is enabled on your printer

[habdk]

Hi boutn,
Thank you very much for your reply. I verified that my printer has SNMP enabled, and I installed the LPR utility. I connected the printer, and the LPR tool can see the printer status etc.
I couldn't find an option in the LPR tool to update the firmware. So I tried Remote Print -> Download and gave it the .bin file. It began to print the bin file (as I expected).
Which option in the LPR utility can be used to upload the firmware?

My CU version is 01.28, and I noticed this in the firmware history notes: (Note) Firmware update function is supported from CU version A1.54 or later. But I guess that is why the normal firmware update tool doesn't work either.

Thanks again for replying, much appreciated.

[habdk]

Hello again,
I decided to re-visit the task of updating the firmware.
I go to the LPR utility and use the "Download..." function. I then select the OKI_MB491_A14.90_0_4_239767.bin file.

The printer starts printing garbage-pages but the display says

"Wait a moment
Executing maintenance"

Google tells me that this message means it's updating firmware. I intentionally only left a few pages in the tray, and nothing more happens when it runs out of paper.

I'm wondering if maybe I should install an older level of firmware first? Does anyone have an old copy of some older firmware around?

Appreciate any input you may have, thanks! :-)