I've had the bad idea to upgrade the firmware of our Epson WF-7840 (version CD17M6 now).

Now, our non epson cartridges are not recognised anymore.

I've search the web about how to downgrade the firmware. I found the procedure, found how to put the printer in "recovery mode" and, on the Epson website, I found the "Recovery Mode Firmware version CB08LC" for the Epson WF-7840.

But it doesn't work...

First problem, the model of the printer does not appear in the "Epson firmware updater" but it sees that a printer is connected.

Second problem, and it is where it stops, when I launch the Update, it fails with a message on the printer's screen "Data file not found".

I tried with my mac (macbook pro 16" m1 max) and with an older macbook pro from 2009 with the same result. I tried with another USB cable and still no luck.

What am I doing wrong?

⟐ Answered 4월 22, 2026 at 8:15 GMT-7

⟐ Marked as duplicate 4월 21, 2026 at 7:57 GMT-7

It is failing to print

⟐ Commented 4월 20, 2026 at 11:48 GMT-7

⟐ Answer accepted 4월 20, 2026 at 8:44 GMT-7

⟐ Answer accepted 4월 18, 2026 at 21:53 GMT-7

I had cleaned the heads at least 10 times. The test page prints ok, but only.

All others print in white.

The noozle check shows yellow, cian and magenta, but no black.

Minha impressora só imprime a página de teste.

Já fiz limpeza de cabeças umas dez vezes. No Nozzle check aparecem as cores mas nada em preto.

Todas as outras tentativas a folha sai em branco.

⟐ Answered 4월 17, 2026 at 0:45 GMT-7

⟐ Answered 4월 16, 2026 at 4:05 GMT-7

I am beyond frustrated and I refuse to reset it up each and every time I have to print. I called Brother and their response was that the printer needs to be within three to five feet of the router (???!?!?). They said that the printers are "very sensitive" yet it's a "wifi issue, not a printer issue".

I never would have spent $150 for a wifi printer that needs to be literally next to my modem to work. I may as well have it wired directly. I have a small condo (1000 square feet) and the printer is in the room next to where my modem is located. It's maybe twenty or thirty feet away. There is no solid wall separating the two rooms--there's a large double doorway between them.

I'm so frustrated and upset that something so new and not inexpensive is useless. Do I have any options to keep the machine from constantly dropping the connection? I read somewhere else about "fixing" the IP address but before I mess with that want to make sure that is the right thing to do. Thanks!

⟐ Commented 4월 13, 2026 at 9:01 GMT-7

Some time ago, I bought a Samsung Xpress C480W printer. I haven't used it much. I've printed about 2,000 times with it.

I haven't used it much. I've printed about 2,000 times with it.

After not using it for a while, when I tried to print, a ghost image appeared at the bottom of the page.

I measured the distance between the ghost image and the original image, and it doesn't match any distance indicated in the manual (19.4 cm).

I replaced the transfer roller and the fuser, but the problem persists.

Does anyone have any idea what the problem might be?

Thank you.

⟐ Answer edited 4월 16, 2026 at 7:26 GMT-7

The printer works beautiful, except for when it isn't used for a couple days, which it will say "Offline". Troubleshooting in Windows 10 just says it's not powered on, but it clearly is. When I check the network status on the printer, it says still connected. I'm unable to ping it when it says offline.

Sometimes rebooting the router will cause it to come back, but usually I have to remove the printer completely, and re-add it manually using the IP Address. It doesn't come up as an addable device for some reason, which is the reason for manually adding it.

One possible fix I found said to go to the port configuration and disable SNMP. (SNMP Fix Tutorial)However, when I click on "Configure Port...", I get an error. Also, the port name is very odd looking.

I have a picture of the error located here = Port error

Is there something I can do to resolve this that I'm not aware of?

Thank you for the response. It makes complete sense.

So I deleted the printer, and re-added it using the hostname instead of the IP address. I have the epson software already installed, and it says all drivers are up to date. When I try to run the Epson Event Manager, with the printer added, it says

And I still get the following error when I try to configure the port =

I will let you know if/when it goes offline again.

This issue started before I ever started using the IP address to add it.

Thank you again for responding.

⟐ Answered 4월 13, 2026 at 5:01 GMT-7

I’m having an issue with my printer showing an error that the waste ink pad (waste ink absorber) is full. The printer stopped working completely because of this.

I tried to open the printer to access the waste ink pads, but I couldn’t reach them—they seem to be located deep inside the printer and not easily accessible.

I need help with:

How to access the waste ink pad inside the printer

Whether there is a way to reset the waste ink counter without full disassembly

If there is any software tool or service mode reset available for this model

Any step-by-step guidance or diagrams would be appreciated.

⟐ Answer edited 4월 12, 2026 at 20:04 GMT-7

⟐ Commented 4월 12, 2026 at 10:10 GMT-7

Hoping some could help!

⟐ Commented 4월 12, 2026 at 4:24 GMT-7

⟐ Answered 4월 12, 2026 at 2:34 GMT-7