Problem downgrading the firmware of an Epson WF-7840

I was able to run the https://ftp.epson.com/drivers/FW_CD08M4.... after I started my WF-7840 in recovery mode connected with a USB cable.

Recovery Mode = power off printer then hold the 4,7, job status and power button. I did not unplug the printer until it would not restart itself from the recovery mode. After the unplug and restart, I had to remove the ink cartridges and reinsert them. After that it worked!

Hi folks,

I have a WF-7840

I really don’t have time to explain this, but I am so discouraged by how badly tech people explain things, I bit the bullet and put together a more comprehensive step by step.

I thought I would help all those other non-tech people out there by posting clear and a layman friendly explanation in proper English. I will give a short version first, then a bit of a longwinded version later which might help some people understand what’s going on, and what each file is for, and hopefully feel more comfortable with the process.  In the end, after you’re done, you’ll realize it’s quite simple and the next time you do it (god forbid), you’ll find it rather easy.

I will also explain some of the file naming discrepancies that are quite confusingly described in other posts. Or rather, I will indicate the proper

I hope I didn’t make any typos below. But if I did, please point them out and I will correct if I have time. Also, looks like the Word formatting got messed up a bit. Sorry about that. No time to figure out formatting.

So, here goes.

“Short” version (see after screenshots for longer version with more explanation):

1.      Download the old Epson recovery files. These are simply the recovery software for an older version of the firmware. Here are the links:

a.      https://ftp.epson.com/drivers/FW_CD08M4....

b.      https://ftp.epson.com/drivers/FW_CD08M4....

2.      Next, Download the current recovery utility tool from Epson’s current WF-7840 support site. This will have a longer name than the files in step 1 above (i.e., FWCH67TL_CD08M4.exe).

a.      https://epson.com/Support/Printers/All-I...

3.      So, now you have the files you need. Next step is to get the old firmware files unpacked from the files downloaded in 1:

a.      Run the old utility downloaded in step 1a (“FW_CD08M4.exe”).  What this does is start the recovery process. Normally you would have your printer in recovery mode during this step (described later), but it’s not necessary right now since you’re just trying to get the old recovery software (which won’t work anymore) to unpack the older firmware into your “temp” folder so you can copy it for later use.

b.      Navigate to C:\Users\”your name here”\AppData\Local\Temp (ensure hidden and system files are visible)

c.      You should now be in:

                                                              i.      C:\Users\”your name here”\AppData\Local\Temp

                                                             ii.      DON’T go into the Epson folder.

                                                           iii.      When you ran the old Recovery utility in step 3a above, a folder called “Firmware Updater()” appeared in the “Temp” folder. Inside it will be the old firmware files. Copy these anywhere you want. This file is called “FWCH67TL.rcx”.

                                                           iv.      Cancel the Recovery update utility. The “Firmware Updater()” folder will disappear. But you got the file you need.

4.      Now you have the old Firmware files saved.

5.      Next you have to attach your printer to a USB printer cable (port located next to the power cable on the back of the printer).

6.      Next you need to put your printer into recovery mode by pressing and holding the following buttons simultaneously:

a.      4,7, job/status, power button

b.      The printer screen will go black, then shortly after some white text indicating it’s in recovery mode will appear.

7.      Next run the software you downloaded in step 2 (current Epson recovery firmware named “FWCH67TL_CD30N1.exe”).  Note, this won’t work if your printer isn’t in recovery mode.

8.      So this does the exact same thing as the old recovery utility software from step 3. It unpacks the firmware into the “Firmware Updater()” folder in the “Temp” folder.  But this time you want to deploy firmware onto your printer. But not yet. First:

9.      You need to replace the new firmware files just unpacked (also called FWCH67TL.rcx) with the old firmware unpacked and saved in step 3.c.iii.. So, replace the firmware that was just unpacked.  You want to replace this newer firmware that was just unpacked into “Firmware Updater()” with the old firmware you saved in step 3.c.iii above (note: keep the newer Recovery Utility software open/running on your computer while doing this or the folder “Firmware Updater()” will disappear).

10.  Once you have replaced these files in the newly created “Firmware Updater() folder, you can finish the last installation steps in the software. It’s pretty user friendly. Just follow the remaining prompts from where you left off before pausing to replace the firmware files with old files.

a.      Don’t select the Network connection type to the printer however. Tick the box next to the USB connection type only.

11.  The newer Epson recovery utility software was essentially tricked into deploying the older firmware you copied into the “Firmware Updater()” folder onto the printer.

12.  The software will then say something similar to “wait for the printer to power itself down”. You’re lucky if the printer actually powers itself down. I clicked “finish” in the software. The software closed, but it looked like my printer was still deploying the firmware onto it’s internal “chip(s)”. The power button was flashing intermittently (but also sometimes solid), and the white text message on the screen wasn’t definitive.  So I walked away for an hour and let it do it’s thing.

13.  When I returned, almost half the lights on my printer were blinking, including error, printer, and many other. Lit up like a Christmas tree.  Quite alarming, but nothing to worry about. Still some non-definitive text on the screen (but new stuff from before). Holding the power button did nothing.

14.  Easy fix.

a.      Unplug.

b.      Plug back in.

c.      Power up by pressing power button.

15.  Printer accepts previously rejected printer cartridges. Everything working properly.

Okay, not that short. Longer version with more explanation below screenshots.

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Screenshots supposed to be here. Will try and get then entered properly, but may appear at bottom, or not at all if there's not option for easily posting screenshots.

Screenshot 1: Firmware Updater() folder does not show up until you run the recovery utilities.

Screenshot 2: When you run the recovery utilities, the folder underlined in red will show up.

Screenshot 3: Epson recovery utility. In this case, the printer is not in recovery mode, and the installed firmware is newer than the “newest” recovery firmware, so the status column shows error messages about “It cannot be updated”. When the printer is in recovery mode, these messages won’t appear, so nothing to worry about.

____________________________________________________________________________________________________________________________________

Long version (see above screenshots for a shorter, more concise version with less explanation):

1.      Download the old Epson recovery files (first link “a” below). This is simply the recovery software for an older version of the firmware. Here are the links:

a.      https://ftp.epson.com/drivers/FW_CD08M4....

b.      https://ftp.epson.com/drivers/FW_CD08M4....

2.      Download the current recovery utility tool from epson’s current WF-7840 support site. This will have a longer name than the files in step 1 above (i.e., FWCH67TL_CD08M4.exe).

a.      https://epson.com/Support/Printers/All-I...

b.      You will find this official, current recovery utility at the following link (but not immediately at the home page the link brings you to). You also need to navigate to:

                                                              i.       “downloads”,

                                                             ii.      Choose your operating system (if not automatically detected by Epson),

                                                           iii.      Then go to the firmware category, and download the recovery utility.

3.      So, now you have the files you need. Next step is to get the old firmware files unpacked from the files downloaded in 1:

a.      Run the old utility downloaded in step 1a (“FW_CD08M4.exe”).  What this does is start the recovery process. Normally you would have your printer in recovery mode during this step (described later), but it’s not necessary right now since you’re just trying to get the old recovery software (which won’t work anymore) to unpack the older firmware into your “temp” folder so you can copy it for later use. Why people just don’t post these older firmware files is beyond me. Maybe it’s a legal issue.

b.      So where is this mysterious temp folder where these firmware files are unpacked?. You can get to the temp folder following the manual way people describe elsewhere in this topic (basically just navigating to C:\Users\”your name here”\AppData\Local\Temp)

c.      You should now be in:

                                                              i.      C:\Users\”your name here”\AppData\Local\Temp

                                                             ii.      DON’T go into the Epson folder. Yes it lives here also in the “temp” folder, but I don’t know why people keep saying to go there. The Recovery Utility doesn’t use it to unpack the old firmware. It creates a new folder in “Temp” with no indication it is an Epson folder (see next step).

                                                           iii.      When you ran the old Recovery utility in step 3a above, a folder called “Firmware Updater()” appeared in the “Temp” folder. Inside it will be the old firmware files. Copy these anywhere you want. I saved them on my dropbox so I never have to go through steps 1a to 1d again if I ever have to do this downgrade over.

                                                           iv.      Cancel the Recovery update utility. The “Firmware Updater()” folder will disappear. But you got the files you need.

a.      If you can’t see the files or folders noted above, make sure hidden and system files are visible. Do a google search for this if you don’t know how. It varies by operating system

4.      Now you have the old Firmware files saved.

5.      Next you have to attach your printer to a USB printer cable (port located next to the power cable on the back of the printer). Epson recommends you unplug other USB devices which is silly. Just unplug other printers or other devices I may not be thinking of that could be damaged. I left my external hard drive plugged in without issue.

6.      Next you need to put your printer into recovery mode by pressing and holding the following buttons simultaneously:

a.      4,7, job/status, power button

b.      The printer screen will go black, then shortly after some white text indicating it’s in recovery mode will appear.

7.      Next run the software you downloaded in step 2 (current Epson recovery firmware named “FWCH67TL_CD30N1.exe”).  Note, this won’t work if your printer isn’t in recovery mode since the “recovery” firmware is likely older than the firmware currently in your printer.  You will just see a window on your computer stating the firmware can’t be “downgraded” if you’re not in recovery mode on the printer.  It will only run properly if you’re in recovery mode on the printer.  It’s possible that Epson may rename this software in newer versions. But as long as you downloaded it from the link in step 2a, or just navigated to Epson’s support page using google, you should be fine.

8.      So this does the exact same thing as the old recovery utility software from step 3. It unpacks the firmware into the same  “Firmware Updater()” folder in the “Temp” folder.  But this time you want to deploy firmware onto your printer. But not yet.

9.      You need to replace the new firmware with the old firmware. So, replace the firmware that was just unpacked using the recovery utility.  You want to replace this newer firmware that was just unpacked into “Firmware Updater()” with the old firmware you saved in step 3.c.iii above (remember, keep the newer Recovery Utility open on your computer while doing this or the folder “Firmware Updater()” will disappear).

10.  Once you have replaced these files in the newly created “Firmware Updater() folder, you can finish the last installation steps in the software. It’s pretty user friendly. Just follow the remaining prompts from where you left off before pausing to replace the firmware files with old files.

a.      Don’t select the Network connection type to the printer however. Tick the box next to the USB connection type (see screenshot below)…except you wont see the “Downgraded(it cannot be updated) message that’s in the screenshot if your printer is in recovery mode).

11.  The newer Epson recovery utility software was essentially tricked into deploying the older firmware you copied into the “Firmware Updater()” folder.

12.  The software will then say something similar to “wait for the printer to power itself down”. You’re lucky if the printer actually powers itself down. I clicked “finish” in the software. The software closed, but it looked like my printer was still deploying the firmware onto it’s internal “chip(s)”. The power button was flashing intermittently (but also sometimes solid), and the white text message on the screen wasn’t definitive.  So I walked away for an hour and let it do it’s thing.

13.  When I returned, almost half the lights on my printer were blinking, including error, printer, and many other. Lit up like a Christmas tree.  Quite alarming, but nothing to worry about. Still some non-definitive text on the screen (but new stuff from before). Holding the power button did nothing.

14.  Easy fix.

a.      Unplug.

b.      Plug back in.

c.      Power up by pressing power button.

15.  Printer accepts previously rejected printer cartridges. Everything working properly.

My printer won’t print after the firm ware update! I have googled and googled and I can’t find any kind of help! Please what can I do to be able to print!?!?

I had this exact problem. Couldn't figure it out for months. Then, suddenly, I tried one last time, but this time I used the firmware update for another similar model, the EC-C7000. The Firmware version is different. But in my disbelief it worked. I'm still in shock. The CD08M4 version firmware update didn't work for me no matter what I did. But for some reason this other CD17M6 did the trick. Epson is a tricky bastard. I urge you to try it. You can find the version I used on the Epson website here:

https://epson.ca/Support/Printers/All-In...

Just be sure to let the printer do it's thing. The lights will flicker randomly, and after about two minutes the printer will turn off on its own. Once that happens you can press the power button and viola....

Good luck and godspeed.

Hello,

Where can I download latest firmware for my Epson WF-7720? version FA27K7 27/07/2020

Thank you,

Firmware CD08M4 Works, however Printer Cartridges Not Recognized is still the prevailing issue. I've attempted the Cart. Removal, Closed Lid for Cart. Reset, and Reinsertion 10 times now. Nothing has worked. Using aftermarket ink of course.

MAC:
Tired and obviously confused today, so I updated the firmware which I never do. To recover, I used the MAC dmg file from Paul Muir above. Saved it to a to new folder somewhere and extracted it (click on dmg file). Then I used Finder to go to Applications, Epson Software, Epson Firmware Updater. Created a "backup" folder and copied the old software to that. Copied the newly extracted dmg files from my backup folder (19_license.txt, Epson Firmware Updater.app and FWCH67TL.efu) to the WF-7840 Series folder.

Then put the printer into recovery mode. Turn off printer. Hold 4, 7 and Job Status button on right side of printer, then hold power button until you get a screen. It came up with a black screen similar to DOS. I then ran the updater using the files I had placed in the WF-7840 Series folder (navigate to folder and click to run on Epson Firmware Updater.app. Follow app steps. It took some time and you need to not turn off the printer. The power button will blink occasionally while waiting. Wait until it turns off by itself. Took about 10 minutes for me. Then I just powered it on, got the unsupported cartridge error. Opened the top and removed and reseated my third party cartridges and that worked for me.

I only wrote this because I could not find a MAC specific solution. I am on Sonoma 14.2.1 and had to read a lot of articles and posts to piece this together for MAC.

But large thanks to Paul for including a MAC file.

Heehaw, it worked, now just if we can get updates to do the same for our smartphones to end this ridiculous inflation.

FYI. If you need the old recovery software for your version OS, all you do is copy the link from 1a from above and replace it with the file name you get from epson, the drive files are all stored in the same directory as: https://ftp.epson.com/drivers/FW_CD08M4....

Replace the last part of this directory file with your OS file name and you will get your recovery updater for your OS. Then complete the rest of steps.